Monday, 26 September 2011

Categories

For More Details, Clich Each Picture

             

         


Sunday, 28 August 2011

USB Flash Drive

A USB flash drive is a data storage device that consists of flash memory with an integrated Universal Serial Bus (USB) interface. USB flash drives are typically removable and rewritable, and physically much smaller than a floppy disk. Most weigh less than 30 g (1 oz). Storage capacities in 2010 can be as large as 256 GB with steady improvements in size and price per capacity expected. Some allow 1 million write or erase cycles and offer a 10-year shelf storage time.
USB flash drives are often used for the same purposes for which floppy disks or CD-ROMs were used. They are smaller, faster, have thousands of times more capacity, and are more durable and reliable because of their lack of moving parts.



Saturday, 27 August 2011

Internet Modem

A modem (modulator-demodulator) is a device that modulates an analog carrier signal to encode digital information, and also demodulates such a carrier signal to decode the transmitted information. The goal is to produce a signal that can be transmitted easily and decoded to reproduce the original digital data.

Modems can be used over any means of transmitting analog signals, from light emitting diodes to radio. The most familiar example is a voice band modem that turns the digital data of a personal computer into modulated electrical signals in the voice frequency range of a telephone channel. These signals can be transmitted over telephone lines and demodulated by another modem at the receiver side to recover the digital data.


Friday, 26 August 2011

Local Area Network (LAN) Card

A network interface controller (also known as a network interface card, network adapter, LAN adapter and by similar terms) is a computer hardware component that connects a computer to a computer network.

Whereas network interface controllers were commonly implemented on expansion cards that plug into a computer bus, the low cost and ubiquity of the Ethernet standard means that most newer computers have a network interface built into the motherboard.




Thursday, 25 August 2011

Video Graphic Adopter (VGA)

Video Graphics Array (VGA) refers specifically to the display hardware first introduced with the IBM PS/2 line of computers in 1987, but through its widespread adoption has also come to mean either an analog computer display standard, the 15-pin D-subminiature VGA connector or the 640×480 resolution itself. While this resolution was superseded in the personal computer market in the 1990s, it is becoming a popular resolution on mobile devices.




Wednesday, 24 August 2011

Hard Disk Drive (HDD)

A hard disk drive (HDD; also hard drive or hard disk) is a non-volatile, random access digital data storage device. It features rotating rigid platters on a motor-driven spindle within a protective enclosure. Data is magnetically read from and written to the platter by read/write heads that float on a film of air above the platters.

Introduced by IBM in 1956, hard disk drives have decreased in cost and physical size over the years while dramatically increasing in capacity. Hard disk drives have been the dominant device for secondary storage of data in general purpose computers since the early 1960s.




Sunday, 14 August 2011

Random Access Memory (RAM)

Random-access memory (RAM) is a form of computer data storage. Today, it takes the form of integrated circuits that allow stored data to be accessed in any order with a worst case performance of constant time. Strictly speaking, modern types of DRAM are therefore not random access, as data is read in bursts, although the name DRAM / RAM has stuck. However, many types of SRAM, ROM, OTP, and NOR flash are still random access even in a strict sense. RAM is often associated with volatile types of memory (such as DRAM memory modules), where its stored information is lost if the power is removed.

There are some types of RAMs;
SDR RAM, DDR RAM, DDR2 RAM, DDR3 RAM.





Tuesday, 2 August 2011

Microprocessor

A microprocessor (abbreviated as ┬ÁP or uP) is a computer processor on a microchip. It's sometimes called a logic chip. A microprocessor is designed to perform arithmetic and logic operations that make use of small number-holding areas called registers. Typical microprocessor operations include adding, subtracting, comparing two numbers, and fetching numbers from one area to another. These operations are the result of a set of instructions that are part of the microprocessor design.



Sunday, 31 July 2011

Motherboard

In personal computers, a motherboard is the central printed circuit board (PCB) in many modern computers and holds many of the crucial components of the system, providing connectors for other peripherals. The motherboard is sometimes alternatively known as the mainboard, system board, or, on Apple computers, the logic board. It is also sometimes casually shortened to mobo.



Saturday, 30 July 2011

Power Supply

A power supply unit (PSU) supplies direct current (DC) power to the other components in a computer. It converts general-purpose alternating current (AC) electric power from the mains (110 V to 120 V at 60 Hz [115 V nominal] in North America, parts of South America, Japan, and Taiwan; 220 V to 240 V at 50 Hz [230 V nominal] in most of the rest of the world) to low-voltage (for a desktop computer: 12 V, 5 V, 5VSB, 3V3, −5 V, and −12 V) DC power for the internal components of the computer. Some power supplies have a switch to select either 230 V or 115 V. Other models are able to accept any voltage and frequency between those limits and some models only operate from one of the two mains supply standards.

Friday, 29 July 2011

Floppy Disk

A floppy disk is a disk storage medium composed of a disk of thin and flexible magnetic storage medium, sealed in a rectangular plastic carrier lined with fabric that removes dust particles. They are read and written by a floppy disk drive (FDD).

Invented by IBM, floppy disks in 3.5-inch (89 mm), 5.25-inch (133 mm) and 8-inch (200 mm) forms were an ubiquitous form of data storage and exchange from the mid-1970s to the 2000s.

Thursday, 28 July 2011

CD / DVD Drive

1. CD-ROM:

CD-ROM an acronym of "Compact Disc Read-only memory") is a pre-pressed compact disc that contains data accessible to, but not writable by, a computer for data storage and music playback. The 1985 “Yellow Book” standard developed by Sony and Philips adapted the format to hold any form of binary data.


3. DVD-ROM:

DVD is an optical disc storage media format, invented and developed by Philips, Sony, Toshiba, and Panasonic in 1995. DVDs offer higher storage capacity than compact discs while having the same dimensions.

Pre-recorded DVDs are mass-produced using molding machines that physically stamp data onto the DVD. Such discs are known as DVD-ROM, because data can only be read and not written nor erased.




3. Combo Drive:

A Combo drive is a type of optical drive that combines CD-R/CD-RW recording capability with the ability to read (but not write) DVD media. The term is used almost exclusively by Apple Inc. The device was created as a mid-range option between a CD burner and a DVD readable, which at the time the Combo drive was introduced was generally an expensive option costing in excess of US$300 a unit.




4. Super Drive:
 
A Super Drive or a DVD recorder (also known as a DVDR, is an optical disc recorder that records video onto blank writeable DVD media. Such devices are available as either installable drives for computers or as standalone components for use in studios or home theater systems.

Wednesday, 27 July 2011

Inside the CPU

If we want to know, what is inside of a Centeral Processing Unit (CPU), then we would remove all its screw and open its both side covers, after all we will find the following parts as shown in pictures.

 



Tuesday, 26 July 2011

Central Processing Unit (CPU)

The central processing unit (CPU) is the portion of a computer system that carries out the instructions of a computer program, and is the primary element carrying out the functions of the computer or other processing device. It carries out each instruction of the program in sequence, to perform the basic arithmetical, logical, and input/output operations of the system. In other words, the CPU is the "brains" of the computer. The term has been in use in the computer industry at least since the early 1960s.


Monday, 25 July 2011

Multimedia Projector

A Multimedia Projector is a device that receives a video signal and projects the corresponding image on a projection screen using a lens system. All video projectors use a very bright light to project the image, and most modern ones can correct any curves, blurriness, and other inconsistencies through manual settings. Video projectors are widely used for many applications such as, conference room presentations, classroom training, home theatre and concerts. Projectors are widely used in many schools and other educational settings, connected to an interactive whiteboard to interactively teach pupils.

Sunday, 24 July 2011

Speakers / Headphone

Speakers:
Computer speakers, or multimedia speakers, are speakers external to a computer, that disable the lower fidelity built-in speaker. They often have a low-power internal amplifier. The standard audio connection is a 3.5 mm (approximately 1/8 inch) stereo jack plug often color-coded lime green (following the PC 99 standard) for computer sound cards. A plug and socket for a two-wire (signal and ground) coaxial cable that is widely used to connect analog audio and video components.


 

Headphones:
Headphones are a pair of small loudspeakers, or less commonly a single speaker, held close to a user's ears and connected to a signal source such as an audio amplifier, radio, CD player or portable media player. They are also known as stereophones, headsets or, colloquially, cans. The in-ear versions are known as earphones or earbuds.



Saturday, 23 July 2011

Printer

1. Deskjet Printer:
An inkjet printer is a type of computer printer 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 up to thousands of dollars.

 

2. Laser Printer:
A laser printer is a common type of computer printer that rapidly produces high quality text and graphics on plain paper. As with digital photocopiers and multifunction printers (MFPs), laser printers employ a xerographic printing process, but differ from analog photocopiers in that the image is produced by the direct scanning of a laser beam across the printer's photoreceptor.


 

3. Plotter:
A plotter is a computer printing device for printing vector graphics. In the past, plotters were widely used in applications such as computer-aided design, though they have generally been replaced with wide-format conventional printers. It is now commonplace to refer to such wide-format printers as "plotters," even though they technically aren't.





Friday, 22 July 2011

Monitor / LCD

1. Monitor:
A Monitor or display (sometimes called a visual display unit) is an electronic visual display for computers. The monitor comprises the display device, circuitry, and an enclosure. The display device in modern monitors is typically a thin film transistor liquid crystal display (TFT-LCD) thin panel, while older monitors use a cathode ray tube about as deep as the screen size.
The first computer monitors used Cathode ray tubes (CRTs), which was the dominant technology until they were replaced by LCD monitors in the 21st Century.


 

2. TFT-LCD Monitor:
Thin film transistor liquid crystal display (TFT-LCD) is a variant of liquid crystal display (LCD) which uses thin-film transistor (TFT) technology to improve image quality (e.g., addressability, contrast). TFT LCD is one type of active matrix LCD, though all LCD-screens are based on TFT active matrix addressing. TFT LCDs are used in television sets, computer monitors, mobile phones, handheld video game systems, personal digital assistants, navigation systems, projectors, etc.


 

3. Touchscreen Monitor:
A touchscreen is an electronic visual display that can detect the presence and location of a touch within the display area. The term generally refers to touching the display of the device with a finger or hand. Touchscreens can also sense other passive objects, such as a stylus. Touchscreens are common in devices such as all-in-one computers, tablet computers, and smartphones.


Thursday, 21 July 2011

Other Input Devices

There are also some other input Devices that works like a mouse and can be use instead of Mouse or Keyboard. These Devices are Trackball, Trackpad, Pen device & Trackpoint.


Wednesday, 20 July 2011

Joystick / Gamepad

In computers, a joystick and gamepad are the cursor control devices used in computer games. The joystick, which got its name from the control stick used by a pilot to control the ailerons and elevators of an airplane, is a hand-held lever that pivots on one end and transmits its coordinates to a computer. It often has one or more push-buttons, called switches, whose position can also be read by the computer.

Joystick:
There are some pictures of Joysticks.

Gamepad:

A gamepad (also called joypad or control pad), is a type of game controller held in the hand, where the digits (especially thumbs) are used to provide input. Gamepads generally feature a set of action buttons handled with the right thumb and a direction controller handled with the left. The direction controller has traditionally been a four-way digital cross.
There are some pictures of Gamepads.




Tuesday, 19 July 2011

Digital Camera / Webcam


A digital camera records and stores photographic images in digital form that can be fed to a computer as the impressions are recorded or stored in the camera for later loading into a computer or printer. Currently, Kodak, Canon, and several other companies make digital cameras.

 

A Webcam is also an input device and it work like a Digital Camera, but it has limited fuctions than Digital Camera. A Webcam is use for Video Chating and also taking photos like digital camera.


Monday, 18 July 2011

Microphone (Mic)

Microphone is an input device that converts sound waves into audio signals. These could be used for sound recording as well as voice chatting through internet.



 

Sunday, 17 July 2011

Scanner


A scanner is an input device that captures images from photographic prints, posters, magazine pages, and similar sources for computer editing and display. Scanners come in hand-held, feed-in, and flatbed types and for scanning black-and-white only, or color.

Very high resolution scanners are used for scanning for high-resolution printing, but lower resolution scanners are adequate for capturing images for computer display.


 

Saturday, 16 July 2011

Keyboard

It is an input device to give computer some input. It is like pen in writing. It is called keyboard because it is comprised of a board with keys installed. Every key send unique information to computer.

A keyboard on a computer is almost identical to a keyboard on a typewriter. Computer keyboards will typically have extra keys, however. Some of these keys (Control, Alt, and F Keys) are meant to be used in conjunction with other keys just like shift on a regular typewriter.

You can see some beautiful Keyboards here.

Friday, 15 July 2011

Mouse

Mouse is a pointing device that works by detecting motion relative to its supporting surface.
There are many types of computer mouse available in the market. They usually have different shapes or buttons, but they work almost in the same fashion.

The mouse first became a widely-used computer tool when Apple Computer made it a standard part of the Apple Macintosh. Today, the mouse is an integral part of the graphical user interface (GUI) of any personal computer.

There are some types/styles of mouse in picture below.

Thursday, 14 July 2011

Devices of Computer

1-Input Devices:


The devices used to give the computer data or commands are called Input devices.An input device is any peripheral (piece of computer hardware equipment) used to provide data and instruction to computer.

Examples:
Mouse, Keyboard, Microphone, Digital Camara, Skanner, Gamepad etc.



2-Output Devices:

The devices to which the computer writes data are called Output devices. Often converts the data into a human readable form. Monitor and printer are output devices.An output device is a hardware used to get the output from the computer. For example head phones are output device and used for listening sound in computer.

Examples:
Monitor, Printer, Speaker etc.




In next lessens we will provide complete information about every input/output device sepratelly.

Wednesday, 13 July 2011

Main Parts of a Computer (2)

This is the second session about the Main Parts of a Computer.
These parts are the necessary parts of a computer but not all parts are compulsory.
We will provide a complete description of every part of computer in our further lessons.


If you have any suggestion about this topic, you can leave a comment.

Tuesday, 12 July 2011

Main Parts of a Computer

Now we are focusing on all next informations about Personal Computers, and this is the first session about the Personal Computer's essentional parts.
These are the Main Parts of a Computer and also its details.


Hope you will like this lessen, if you have any question, please post a comment.

Monday, 11 July 2011

Types of Computers

There are five basic types of Computers.

1-Super Computers:

A supercomputer is a computer that performs at or near the currently highest operational rate for computers. A supercomputer is typically used for scientific and engineering applications that must handle very large databases or do a great amount of computation.


2-Mainframe Computers:

Mainframes are computers where all the processing is done centrally, and the user terminals are called "dumb terminals" since they only input and output (and do not process).

Mainframes are computers used mainly by large organizations for critical applications, typically bulk data processing such as census. Examples: banks, airlines, insurance companies, and colleges.



4-Personal Computers:

It is also known as a Microcomputer. Its physical characteristics and low cost are appealing and useful for its users. Throughout the 1970s and 1980s, home computers were developed for household use, offering some personal productivity, programming and games, while somewhat larger and more expensive systems (although still low-cost compared with minicomputers and mainframes) were aimed for office and small business use.


5-Portable Computers:


Portable computer is a personal computer that is designed to be easily transported and relocated, but is larger and less convenient to transport than a notebook computer. The earliest PCs designed for easy transport were called portables. As the size and weight of most portables decreased, they became known as laptop computer and later as notebookcomputer.


3-Micro Computers:

PDA (personal digital assistant) is a term for any small mobile hand-held device that
provides computing and information storage and retrieval capabilities for personal or
business use, often for keeping schedule calendars and address book information handy.