Power Connector and Voltage Regulator

Power Connectors:-

     
                The motherboard has a socket to attach the power cables coming from the power supply. ATX form factor motherboards  and power supplies use a single 20-wire motherboard power cable. All others use a pair or 6-wire cables.

                     The cables are connected to the motherboard so that the black wires are together in the middle. This connector is usually found near the back right-hand side of the motherboard, near the power supply.

Voltage Regulators:-

       In old days, devices used to run on same voltage of 5V. The arrival if processors and other devices  running at different voltages led to the necessity of motherboards. These regulators reduce the 5V signal to those voltages typically needed by processors: 3.3V or lower.

        Processor manufacturers fit in a dual voltage scheme into their latest designs. The processor is fed two voltages: the external or "I/O" voltage is typically 3.3V, while the internal or "core" voltage is lower: usually 2.8 to 3.2 volts. The voltage regulator is responsible for generating the correct voltage for the processor.

       The voltage regulator can normally be identified by the large heat-sinks that are placed on it; Voltage conversion generates a great deal of heat. On many motherboards, the cooling level of the entire system case is important to ensure that the voltage regulators are cooled satisfactorily. Overheating regulators can cause lockups and other problems.

Motherboard Components(Bus)

Why Bus:-
           A personal computer may transfer data from disk to CPU, from CPU to memory, or from memory to the display adapter. A PC cannot afford to have separate circuits between every pair of devices. A mechanical switch, like the old phone systems used, would be too slow. So we can use bus.

Bus:-
         

              The Bus is simply a common set of wires that connect all the computer devices and chips together. (or) A bus is a common pathway across which data can travel within the computer. This pathway is used for communication and can be established between two or more computer elements. A PC has many kinds of buses, including the following:

•  Processor bus
•  Address bus
•  I/O bus
•  Memory bus

Processor Bus:-
         The processor bus is a communication pathway between the CPU and immediate support chips. These support chips are usually called the chipset in modern systems. This bus is used to transfer data between the CPU and the main system bus.

Address Bus:-
        The address bus actually is a subset of the processor and memory buses. It is used to indicate what address in memory or what address on the system bus are to be used in a data transfer operation.
The size of the memory bus also controls the amount of memory that the CPU can address directly.

Memory Bus:-
        The memory bus is used to transfer information between the CPU and main memory(RAM)  in your system. This bus is either a part of the processor bus itself, or in most cases it is implemented separately by a dedicated chipset that is responsible for transferring information between the processor bus and the memory bus.

I/O Bus:-
       All the motherboards have one or more system I/O buses that are used to expand the computer's capabilities. These buses work closely with expansion cards. The slots in the back of the machine are where expansion cards are placed. These slots allow you to expand the capabilities of your machine in many different ways, and the proliferation of both general purpose and very specific expansion cards is part of the success story of the PC platform.

         Most modern PCs have two different types of bus slots. The first is the standard ISA (Industry Standard Architecture) slot; most PCs have 3 or 4 of these. These slots have two connected sections and start about a half-inch from the back of the motherboard, extending to around its middle. This is the oldest  bus type and is used for cards that don't require a lot of speed: for example, sound cards and modems. Older systems may have ISA slots with only a single connector piece on each; these are 8-bit ISA slots and will only support 8-bit ISA cards.

Motherboard components

Motherboard components:-

         There are many components, which is placed in motherboard. The following are the most important components of motherboard.

 ROM:-
             
              All motherboards include a small block of Read Only Memory (ROM)  which is different from the main system memory used for loading and running software. The ROM contains the PC's Basic Input/Output System(BIOS). This offers two advantages: the code and data in the ROM BIOS need not be reloaded each time the computer is started, and they cannot be corrupted by wayward applications that write into the wrong part of memory.

              A Flash upgrade-able BIOS may be updated via a floppy diskette to ensure future compatibility  with new chips, add-on cards, etc.

BIOS:-

          BIOS (Basic Input/Output System), is also known as ROM BIOS, or System BIOS. It is a chip located on all motherboards that contain instructions and setup for how your system should boot and how it operates. 

            The BIOS includes instructions on how to load basic computer hardware and includes a test referred to as a POST (Power On Self Test) that helps verify the computer meets requirements to boot up properly. If the computer does not pass the POST, you will receive a combination of beeps indicating what is malfunctioning within the computer.

Four main functions of BIOS:-

POST:-
          
          Test the computer hardware and make sure no errors exist before loading the operating system.                  Additional information on the POST can be found on our POST and Beep Codes page.

Bootstrap Loader:-
          
          Locate the operating system. If a capable operating system is located, the BIOS will pass control to it.

BIOS drivers:-
          
           Low level drivers that give the computer basic operational control over your computer's hardware.

BIOS or CMOS Setup:- 

           Configuration program that allows you to configure hardware settings including system settings such as computer passwords, time, and date.

Processor Sockets or Slots:-

             The motherboard has one or more sockets or slots to hold the processor. Single processor motherboards are by far the most common, but dual processor boards are not hard to find. The type of socket or slot used dictates the type of processor that can be used by the motherboard. Not surprisingly, the standards for processor socket and slot have been generally defined by Intel ( a leading company in designing and manufacturing processors and motherboards). 

             Older Intel processors, up to the Pentium Pro, use a square shaped socket for the processor . The latest processors from Intel, starting with the Pentium  II, are mounted on a daughter-board, which plugs into a special type slot, known as SEC(Single Edge Connector) slot, to connect to the motherboard.

Memory Socket:-

              Most motherboards today come with between 2 and 8 sockets for the insertion of memory. These are usually either SIMMs(Single Inline Memory Modules) or DIMMs(Dual Inline Memory Modules). These sockets can be of different sizes.

                The motherboard usually labels these sockets "SIMM0" through "SIMM7" or "DIMM1" through "DIMM3", etc. The sockets are almost always filled starting with the lowest numbered socket first. Most Pentium class or higher motherboards require SIMMs to be inserted in pairs, but DIMMs may be inserted individually.

Cache and/or cache Sockets:-

                Cache is a high-speed access area that can be either a reserved section of main memory or a storage device. Virtually all newer Pentium class motherboards come with either integrated secondary cache or sockets for secondary cache to be inserted. Also called "Level 2" or "L2" cache, secondary cache is high speed memory that is used to buffer processor requests to the regular system memory.

                  256 KB or 512 KB of cache is most common. 1MB and higher cache are now available in the market. Motherboards for Pentium Pro and Pentium II PCs don't have level 2 cache on them; it is already integrated into the processor itself for the Pentium Pro, and into the processor package for the Pentium II.

Introduction to motherboard

Motherboard:-

              The motherboard (also known as  mainboard, system board, planar board or logic board, or colloquially, a mobo) is the main circuit board inside the PC. It holds the processor, memory and expansion slots and connects directly or indirectly to every part of the PC. It's made up of a chipset, some code in ROM and the various interconnections or buses.

              PC designs today use many different buses to link their various components. Wide, high-speed buses are difficult and expensive to produce: the signals travel at such a rate that even distances of just a few centimeters cause timing problems, while the metal tracks on the circuit board act as miniature radio antennae, transmitting electromagnetic noise that introduces interference with signals elsewhere in the system.

               For these reasons, PC design engineers try to keep the fastest buses confined to the smallest area of the motherboard and use slower, more robust buses, for other parts.

                  A motherboard is the main printed circuit board (PCB) found in computers and other expandable systems. It holds many of the crucial electronic components of the system, such as the central processing unit (CPU) andmemory, and provides connectors for other peripherals. Unlike a backplane, a motherboard contains significant sub-systems such as the CPU.

               

                Motherboard specifically refers to a PCB with expansion capability - the board is the "mother" of all components attached to it, which often include sound cards, video cards, network cards, hard drives or other forms of persistent storage, TV tuner cards, cards providing extra USB or Firewire slots, and a variety of other custom components.

Design for motherboard:-

                A motherboard provides the electrical connections by which the other components of the system communicate. Unlike a backplane, it also connects the central processing unit and hosts other subsystems and devices.

              A typical desktop computer has its microprocessor, main memory, and other essential components connected to the motherboard. Other components such as external storage, controllers for video display and sound, and peripheral devices may be attached to the motherboard as plug-in cards or via cables, in  modern        

computers it is increasingly common to integrate some of these peripherals into the motherboard itself.

             An important component of a motherboard is the microprocessor's supporting chipset, which provides the supporting interfaces between the CPU and the various buses and external components. This chipset determines, to an extent, the features and capabilities of the motherboard.      

C programing style

Programming style:-

•       C is a free form language.

•       Write the program in lowercase letters. C program statements are written in lower case letters. Uppercase letters are used only for symbolic constants.

•       Braces ({&}) groups program statement together and mark the beginning the end of function.

•       A proper indentation of braces and statements would make a program easier to read and debug.

•       Since C is a free-form language, we can group statements together on one line.

• The statements:

                           a=b;
                           x=y+1;
                           z=a+x;
               
                      can be written on one line as a=b; x=y+1; z=a+x;

• In the program:

                       main()
                      {
                                printf("Hello C");
                         }
                       can be written in one line as

                               main() { printf("Hello C"); }

•         This style makes the program more difficult to understand and should not be used

Features of C Language

Features or Advantage of C:-

• C is a structured programming language. The objective of a structured programming is to provide methodology in which, the user may develop programs quickly with less mistakes.

• Further, it increases the readability of the program and finally the flexibility of the program is improved to the maximum, which helps the programmer to modify the program without affecting the other portion of the program.

• It is a disciplined approach towards the programming that promotes clear, efficient and error-free programming.

• The structures such as sequence, condition and loop structure are incorporated in the C programming language.

• These structures help the programmer to avoid the undesirable statement called 'goto' statement. The 'goto' statement is an unconditional statement which leads to unstructured programming.

• C is a case-sensitive language i.e C recognizes uppercase and lowercase characters separately. For example, declaring the variable by the name 'add'  is different from 'ADD' or 'Add'. All the three variables are different and unique. Case-sensitiveness leads to a rich character set.

• Portability

• Implemented on many diverse systems
• Implemented on wide variety of hardware
• Defined libraries are themselves portable
• Applications are portable
• Programs are portable

• Powerful
• Completeness – business to scientific applications
• Flexibility – preprocessor, conditional compilation, header files

• C can reference a memory location by means of its address with the help of pointers and allows the user for manipulating Bits(Binary Digits).

• Every statement in the C program should necessarily end with a semicolon. This character is called as the statement delimiter.

Introduction about C Programming

The Art of Programming:-

•             Programming is the technique of defining logic for solving a particular problem. The logic is explained by a series of statements that are usually executed one after other. 

•             The primary objective for writing a program to achieve the desired output. The programmer should first understand what output should he/she produce and how the information should be placed in the output screen.

•             Secondly, the programmer should identify the various inputs that are supplied for obtaining the output.

•             Thirdly, the programmer should take into consideration the constraints or conditions, which affect the output of the program.

C Programming:-

•     C is a general purpose programming language and which is initially developed by Dennis Ritchie in the year of 1972 at AT& BELL laboratories. 

•    It is a structured programming language. C is called a middle-level language( a third term which is a combination of High level and Low level language) because C possess the features of the second and third generation languages.

• C is a highly portable language, that is, a C source program written on one computer can be compiled and executed  on a different computer with less or no modification in the source code.

•  It can be viewed as group of building blocks called functions.

• A function is a subroutine that may includes one or more statements designed to perform specific task. To write a C program, we first create functions and then put them together.

• C is a powerful language. Comments in C provides easy readability.

                     The following diagram will show the overview of C Program:-

Documentation section

Link section

Definition section

Global declaration section

Main ( ) function section  {                     Declaration part                     Executable part }

Subprogram section { Function_1( ) {   } Function_2() {  } }

             

              A C program may contain one or more section . The following topics will give the details about the sections in the C Program.

Documentation section:- 

                

          Documentation section consists of a set of comment line giving the name of the program, the author and other details, which the programmer would like to use later.

Link section:-

         The link section will provide instructions to the compiler to link functions from the system library. The definition section defines all symbolic constants.

Global Declaration section:-

         There are some variable that are used in more than one function. Such a variable are called global variable and are declared in the global declaration section that is outside of all functions.

        This section also declares all the user defined functions.              

Main Function Section:-

        Every C program must have one main () function section. This section contains two parts. They are:

•        Declaration part
•        Executable part

Declaration part:-

        In the declaration part declare all the variables used in the executable part. There is at least one statement in the executable part.

         These two parts must appear between the opening  and closing brace. The closing brace of main function section is the logical end of the program. All statements in declaration and executable part end with semicolon. 

Sub program section:-

         It contains all the user-defined functions that are called in the main function. User defined functions are generally placed immediately after the main function, although they appear in any order. All sections other than main function are optional.

Detail about printer with latest version

Printer:-

         The printer is a device that produce images( Number,Alphabets,Graphs,etc.)on paper. After creating document on the computer, you can send it to the printer for printing its hard copy which is generally called printouts. The speed of the printer is rated either by PPM(Pages Per Minute)or by CPS(Character Per Second). Printers are available in to two flavors-Color and Black and White. Color printers are more expensive than black and white printers.

         Ever since the computer proved itself as an integral part of human society, printers too did not lag behind. with better research and technology, printers start appearing in various shapes, size and categories with faster printing capability. But their working principles are still the same regardless to their categories. All printers have three subsystem:

•      Paper Transportation Subsystem
•      Marketing Subsystem
•      Printing Subsystem or Print Engine.

 Print Speed:-
       
           A printers speed is measured in either the Number of Character per Second(CPS) or the Pages Per Minute  (PPM) the printer can produce. However, these two measurements are rarely used together. Character Per Second is used for printers that forms characters one at a time, such as inkjet and laser printers. Large printers that print an entire line at once(line printers), such as those used with mainframe computers, use Lines Per Minute(LPM) as their print per rating.        

Different types of printer:-

           

             There are many types of printers. But they are generally divided into two types. They are

• Impact printers 
• Non-Impact printers

Impact printer:-

    

         In this  pins strike against a ribbon and paper to print the text. This mechanism is known as electro-mechanical mechanism. There are two types of Impact printers. They are given below

• Character printer
• Line printer

Character printer:-

       It prints only one character at a time. It has relatively slower speed. Eg. Of them are Dot matrix printers.

Dot Matrix Printer :-

               Dot matrix printer is a printer which uses dots to print letter and even pictures. Dot matrix printers can only print one color and use a ribbon similar to a typewriter. Dot matrix printers are still used today in some businesses since you can print 2 part forms and it prints all the way to the second page. 

                It  is also called as impact matrix printer and it is a type of computer printing which uses a print head that runs an up and down motion, on the page and prints by impact, striking an ink-soaked cloth ribbon against the paper, much like the print mechanism on a typewriter.

    

Line printer:-

                 as the name implies, print an entire line of text at a time. Three principal designs existed. In drum printers, a drum carries the entire character set of the printer repeated in each column that is to be printed. In chain printers, also known as train printers, the character set is arranged multiple times around a chain that travels horizontally past the print line. In either case, to print a line, precisely timed hammers strike against the back of the paper at the exact moment that the correct character to be printed is passing in front of the paper. The paper presses forward against a ribbon which then presses against the character form and the impression of the character form is printed onto the paper. The example for line printer is Drum printer.

Drum printer:-

                In a typical drum printer design, a fixed font character set is engraved onto the periphery of a number of print wheels, the number matching the number of columns (letters in a line) the printer could print. The wheels, joined to form a large drum (cylinder), spin at high speed and paper and an inked ribbon is stepped (moved) past the print position. As the desired character for each column passes the print position, a hammer strikes the paper from the rear and presses the paper against the ribbon and the drum, causing the desired character to be recorded on the continuous paper. Because the drum carrying the letterforms (characters) remains in constant motion, the strike-and-retreat action of the hammers had to be very fast. Typically, they were driven by voice coils mounted on the moving part of the hammer.

Non-Impact printer:-

                   There printers use non-Impact technology such as ink-jet or laser technology. There printers provide better quality of O/P at higher speed. These printers are of two types :

•         Character printer 
•          Page printer

Page printer:-

       A page printer is a type of computer printer that prints on cut sheet paper. A modern page printer may use any of various technologies, such as laser, LED or inkjet. Most modern computer printers are page printers.

Laser printer:-

           Laser printing is a digital printing process that rapidly produces high quality text and graphics on plain paper. It is a type of printer that utilizes a laser beam to produce an image on a drum. The light of the laser alters the electrical charge on the drum wherever it hits. The drum is then rolled through a reservoir of toner, which is picked up by the charged portions of the drum. Finally, the toner is transferred to the paper through a combination of heat and pressure.

            This is also the way copy machines work. Because an entire page is transmitted to a drum before the toner is applied, laser printers are sometimes called page printers. There are two other types of page printers that fall under the category of laser printers even though they do not use lasers at all. One uses an array of LEDs to expose the drum and the other uses LCDs. Once the drum is charged, however, they both operate like a real laser printer. One of the chief characteristics of laser printers is their resolution – how many dots per inch (dpi) they lay down.

               The available resolutions range from 300 dpi at the low end to 1,200 dpi at the high end. In addition to text, laser printers are very adept at printing graphics, so you need significant amounts of memory in the printer to print high-resolution graphics. To print a full-page graphic at 300 dpi, for example, you need at least 1 MB (megabyte) of printer RAM. For a 600 dpi graphic, you need at least 4 MB RAM.

              Because laser printers are non-impact printers, they are much quieter than dotmatrix or daisy-wheel printers. They are also relatively fast, although not as fast as some dot-matrix or daisy-wheel printers. The speed of laser printers ranges from about 4 to 20 pages of text per minute (ppm). A typical rate of 6ppm is equivalent to about 40 characters per second (cps).

LED Printer:-

                   An LED printer is a type of computer printer similar to laser printer. LED technology uses a light-emitting diode array as a light source in the printhead instead of the laser used in laser printers and, more generally, in the xerography process. The LED bar pulse-flashes across the entire page width and creates the image on the print drum or belt as it moves past.
LEDs are more efficient and reliable than conventional laser printers, since they have fewer moving parts, allowing for less mechanical wear. Depending on design, LED printers can have faster rates of print than some laser-based designs, and are generally cheaper to manufacture. In contrast to LED printers, Laser printers have to rely on elaborate combinations of rotating mirrors and lenses that must remain in alignment throughout their use. The laser scans from one end of a line to another, then starts on the next line in a much more cumbersome way than with a LED printhead which has no moving parts.

Inkjet printer:-

                    Inkjet printing is a type of computer printing that creates a digital image by propelling droplets of ink onto paper. Inkjet printers are the most commonly used type of printer, and range from small inexpensive consumer models to very large professional machines that can cost tens of thousands of dollars. Four manufacturers account for the majority of inkjet printer sales: Canon, HP, Epson, and Lexmark. Magnetized plates in the ink's path direct the ink onto the paper in the desired shapes. It is capable of producing high quality print approaching that produced by laser printers. A typical ink-jet printer provides a resolution of 600 dots per inch, although some newer models offer higher resolutions.

Speed: Given in Pages per Minute (PPM) the higher the PPM the more pages they can print. Most ink-jet printers offer different speeds depending on the quality of print desired.

Print quality: 

                     

                       Determined by the DPI Dot Per Inch Example 2440 x 1220 DPI (Vertical and Horizontal DPI) The higher the DPI the better in terms of print quality.

Ink:    Ink-Jet Printers use Ink Cartridges (hidden cost)

                      In general, the price of ink-jet printers is lower than that of laser printers. However, they are also considerably slower. Another drawback of ink-jet printers is that they require a special type of ink that is apt to smudge on inexpensive copier paper. 

                       Because ink-jet printers require smaller mechanical parts than laser printers, they are especially popular as portable printers. In addition, color ink-jet printers provide an inexpensive way to print full-color documents.

Latest printer(In 2013):-

HP Officejet Pro 8600 Plus e-All-in-One Printer - N911g (CM750A) - Specifications
                    
                There was a time not too long ago when the typical home office had a separate machine for copying, printing and scanning. Those days are gone. Today’s multifunctional printers offer a variety of features, consolidating all those devices into one, saving time and space. Many all-in-one printers go beyond the typical printer/scanner/copier/fax combo and may include memory card slots, allowing for easy printing of photos, as well as built-in wireless capabilities for printing on a network.

Since your all-in-one printer is just that – all-in-one – there is only one cable needed to connect it to the computer. It also only requires one power outlet. All-in-one printers are available in both inkjet and laser technologies. Inkjets will typically cost less than laser, although laser printers are decreasing in price as they become more popular with the average consumer.

Complete information about scanner with latest version

Scanner:-
   
                     The Scanner is a device that can transfer typed or handwritten texts,graphs, diagrams and photographs to the computer. Instead of making a duplicate copy on paper of the required data or photograph, scanner stores them in the memory of the computer. Scanners find their use in a wide variety of jobs. They  can be used for storing photographs and important documents in their original forms. They may also be used to take in enormous text material that otherwise would be very tedious if typed manually.

                                      It  converts the images, printed text, handwriting, or an object in  to a digital image. Common examples found in offices are variations of the desktop scanner where the document is placed on a glass window for scanning. 

Different types of scanner:-
                           
                                    The common types of scanners we see today are flatbed scanners, handheld scanners, sheetfed scanners, image scanners etc. The following topics will give the different types of scanner with short explanation about them.

                          

Transparency Scanner:-

                       
                        Transparency scanners allow you to scan everything from 35mm slides all the way up to 4x5-in. transparencies. These scanners are targeted to professionals only and thus cost quite a bit. In fact, these high-end transparency scanners are muscling-in on the once exclusive domain of drum scanners by offering more features, better software, and faster scanning time. Slide scanners cost a lot more than the relatively inexpensive flatbed transparency option. For those who may need only an occasional transparency scanned, a flatbed with transparency adapter is the way to go. But if you scan a lot of transparencies, then the only equipment that offers the best quality scans are dedicated transparency scanners.


Sheetfed Scanner:-

                                 In sheetfed scanners, the document that is supposed to be scanned is fed into the horizontal or vertical slot provided in the scanner. The vital components of sheetfed scanner are the sheet-feeder, scanning module and calibration sheet. Such scanners are most often used to scan single page documents. It can't be used to scan thicker objects, like books, which turns out to be its major drawback.

Handheld Scanners:-
                                  
                                 A handheld scanner is a small manual scanning device which is moved over the object that need to be scanned. For instance, if a document needs to be scanned, the handheld scanner has to be dragged over the document. Using a handheld scanner can prove to be a cumbersome task, as the hand needs to be steady all the time. Slight movement of the hand can lead to distortion of the image. One of the most utilized handheld scanner is the barcode scanner, typically used in shopping stores to valuate goods.

                                 These scanners are useful for their portability and low price. It generally plug into a computer's printing port, as opposed to a SCSI port, allowing them to be easily shared from workstation to workstation. Many people find them ideal for use with a notebook or laptop. Unfortunately, hand scanners are less accurate than flatbeds because they have weaker light sources and often produce uneven scans - courtesy of the unsteadiness of your hand or the surface you're standing on. Many hand scanners now offer an alignment template to help guide you when scanning. At least one manufacturer ships a motorized "self-propelled" unit to help stabilize its scanner.
High-end hand scanners offer 400 spi resolution and 24-bit color - allowing you to achieve reasonably high-quality results. But their 4" to 5" wide scan head forces you to make multiple passes to scan even average-sized documents. You'll need to use the supplied stitching software to merge these partial scans back together again - a time consuming task.

Drum Scanner:-

                                   Professional color trade shops wouldn't think of using anything less than a drum scanner for producing color separations for high-end printing. Instead of using CCD(Charge Coupled Device) technology, drum scanners use PMT (Photo Multiplier Tube) technology for greater dynamic range and color accuracy. They also cost an arm and a leg, Nevertheless, drum scanners offer features not available to desktop scanners such as direct conversion to CMYK(Cyan Magenta Yellow Black) , auto sharpening, batch scanning, greater dynamic range, and huge image scanning areas. Ironically, most drum scanners don"t support preview mode - drum scanner operators are more interested in numbers than what the see with their eyes. Yet what truly sets drum scanners apart is their increased productivity. Since the process of scanning to CMYK is automated, drum scanners can produce more scans per hour than a desktop unit.

Digital Cameras:-

                               Digital cameras allow you to shoot 3-D objects, much like a regular camera, except you don't have to wait for film developing and processing. Portable units are presently limited in storage and image size. Studio-only units offer larger image size and dynamic range, but require attachment to a host computer - hardly a portable solution. In the future, high-resolution, high-quality, portable units will surely come--they just aren't here now.


Photo Scanner:-

                               It is mostly used to scan photographs. High resolution and color depth are the most vital requirements for scanning photographs, and photo scanner provides the same. If the motive of buying a scanner is to digitize film negatives and slides, then the photo scanner is the best option. They are specially designed to work on slides and negatives. The in-built software in some photo scanners can also help in cleaning old photographs.

Film Scanner:-

                             A film scanner is utilized to scan photographic films directly into a computer. The photographer has direct control over certain aspects, such as cropping, ratio of original image on the film, etc. Some film scanners have specialized software through which it is possible to minimize scratches and improve the color quality. Low-end film scanners most often accept 35 mm film strips while the high-end scanners have interchangeable film loaders which can accept 35 mm strips or 120 mm ones, or individual slides.

Portable Scanners:-

                            Being small in size, portable scanners can be easily carried with oneself anywhere. Some of these are as small as your PDAs, hence, can be easily carried in the pockets. They are of great help when it comes to text document scanning. Their drawback though, is their limitation as far as resolution is concerned. They cannot be used for scanning photographs or other such applications which require high resolution scanning.

Latest scanner(In 2013):-


Flatbed Scanner:-


                 Flatbed scanners have become quite powerful, compact and affordable. In this site, we review entry-level scanners based on common-sense evaluation criteria in order to arrive at product recommendations. It is made up of a glass pane and a moving optical CIS(Contact Image Sensor) or CCD(Charge-Coupled Device) array. The pane is illuminated with the help of bright light planted underneath it. The image which is to be scanned is then placed on the glass pane. The sensor and the source of light move across the glass pane to scan the document and produce its digital copy.
         Careful consideration of the features in the most affordable flatbed scanners reveals a dramatic continuum of capabilities. How should we choose? The most direct analytical approach is to consider – in relationship to your specific situation – the hardware and software attributes, the ease of use and the vendor’s help and support.

Complete information about mouse latest versions

MOUSE:-

                         A mouse(In plural Mice) is a small object, designed to fit nearly under your palm. It has two main   function :

•  You can use it to move a cursor on the screen in all directions(left,right,up,down or diagonal)
• Select the items to displayed on the screen.

Operations of Mouse:-

                       Mouse is a pointing device whose shape resembles an actual mouse. This hand-held  device allows you to control your computer without typing instructions form the keyboard. A mouse has a rubber ball(tracking ball) embedded at its lower side, and buttons on its upper side (top). This ball actually controls the movement of pointer on the computer screen.

                  

                          Every mouse has one primary button (left button) and one secondary button (right button). The primary button is used to carry out the  most tasks, whereas secondary button is used in special cases only. You can select commands and options by positioning the tip of the arrow over the desired choice and clicking the primary mouse button.

                            

                           Working on a computer through a mouse is easy and faster as compared to the keyboard. The mouse is important, particularly, for Graphical User Interfaces(GUI). Because in this case you can simply point options and then by a click of a mouse button you can reach there. Such application are  often called    Point-and-Click programs. It is useful in MS Paint, CorelDraw and Photoshop. 

How to use:-

                          Before you use a mouse, make sure that it is placed on a flat surface so that you can move it easily.To get a firm grip over the mouse, it is better to keep it on a rectangular pad. This would also ensure its smooth movement. The rectangular pad is called mouse-pad.

Different Types of Mouse:-

                                 We have seen the dramatic evolution in  technological arena. Various types of mouse are available in market and the selection solely depends on your requirement. Let’s take a quick look at the available options:

Mechanical mouse:-

                              

                            A hard rubber ball that rolls as the mouse is moved. Sensors inside the mouse body detect the movement and translate it into information that the computer interprets.

                           

                           Also called as the ball mouse, a mechanical mouse has rubber or metal ball on it’s underside. When the ball rolls, mechanical sensors inside the mouse detect the direction and move the pointer on the screen of the PC. This type of mouse requires a flat surface or a mouse pad to work efficiently. One of the drawbacks of the device is that it is more prone to attracting dust.

Optical-mechanical Mouse:-
                             
                             It uses an LED sensor to detect tabletop movement and then sends off that information to the computer for merry munching.
                             
                         Optomechanical or optical-mechanical mouse is same as the mechanical mouse except that the sensors used in it are optical and not mechanical. The device is a combination of optical and mechanical technologies, wherein, the ball is present but the mouse movement is detected optically leading to more accuracy.

Lazer Mouse:-

                           A laser mouse is an optical mouse that uses coherent (laser) light. It is a new generation mouse with two necessary components – light emitter and light detector. A laser mouse uses laser as the light emitter and has a precise scanning of mouse movement. You will find a laser mouse ranging anywhere between 1000-5700 dots-per-inch.


3D-Mouse:-
                            3D mouse are devices, that allows an intuitive navigation of  three-dimension models and work with both hands simultaneously. The typical interface for the keyboard and mouse 2D offers a navigation of universal applications, such as web browsers, email and others, in which the scroll is a key tool for easy navigation. The 3D CAD applications requires the possibility of rotation, move, zoom and zoom down 3D models at the same time. This condition of 6 degrees of freedom in movement is completely unavailable in the case of the mouse which uses only 2 degrees of freedom of movement. For example, the user is able to move the first model. Then they needs to change the mode to zoom, and then switch the mode for the rotation. For comparison, all three elements - move, rotate and zoom - can be achieved in one, smooth movement of the 3D mouse.  Probably the best known example would be 3Dconnexion/Logitech's SpaceMouse from the early 1990s. In the late 1990s Kantek introduced the 3D RingMouse. This wireless mouse was worn on a ring around a finger, which enabled the thumb to access three buttons. The mouse was tracked in three dimensions by a base station. Despite a certain appeal, it was finally discontinued because it did not provide sufficient resolution.

                                     A recent consumer 3D pointing device is the Wii Remote. While primarily a motion-sensing device (that is, it can determine its orientation and direction of movement), Wii Remote can also detect its spatial position by comparing the distance and position of the lights from the IR emitter using its integrated IR camera (since the nunchuk accessory lacks a camera, it can only tell its current heading and orientation). The obvious drawback to this approach is that it can only produce spatial coordinates while its camera can see the sensor bar. A mouse-related controller called the SpaceBall has a ball placed above the work surface that can easily be gripped. With spring-loaded centering, it sends both translational as well as angular displacements on all six axes, in both directions for each. In November 2010 a German Company called Axsotic introduced a new concept of 3D mouse called 3D Spheric Mouse. This new concept of a true six degree-of-freedom input device uses a ball to rotate in 3 axes without any limitations.


Tactile mouse:-

                          In 2000, Logitech introduced the "tactile mouse", which contained a small actuator that made the mouse vibrate. Such a mouse can augment user-interfaces with haptic feedback, such as giving feedback when crossing a window boundary. To surf by touch requires the user to be able to feel depth or hardness; this ability was realized with the first electrorheological tactile mouse but never marketed.

Ergonomic mouse:-

                          As the name suggests, this type of mouse is intended to provide optimum comfort and avoid injuries such as carpal tunnel syndrome, arthritis and other repetitive strain injuries. It is designed to fit natural hand position and the movements, to reduce discomfort.



Gaming mouse:-

                         These mouse are specifically designed for use in computer games. They typically employ a wide array of controls and buttons and have designs that differ radically from traditional mouse. It is also common for gaming mouse, especially those designed for use in real-time strategy games such as StarCraft or League of Legends, to have a relatively high sensitivity, measured in dots per inch (DPI). 

Latest Mouse(in 2013):-


 6400dpi 4G Laser Sensor:-
                                    It is the most precise sensor ever outfitted in a mobile gaming mouse, the Razer Orochi’s 6400dpi 4G laser sensor takes out the competition with deadly accuracy.

           
 Wired / Wireless Bluetooth Connectivity:-

                                     Achieve both the frenzy of wired and the freedom of wireless play with the Razer Orochi. It performs equally well both wired and through wireless Bluetooth 3.0 connectivity found in most laptops.

  Extended battery life:-

                                    The Razer Orochi is powered by two AA batteries, and optimized for extended life. Achieve up to 30 hours of continuous gameplay, or 3 months of normal usage, twice of it’s predecessor.