A typical personal computer consists of a case or chassis in desktop or tower shape and the following parts:
Typical Motherboard found in a computer
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Typical Motherboard found in a computer

* Motherboard or system board with slots for expansion cards and holding parts including:
o Central processing unit (CPU)
o Random Access Memory (RAM) - for program execution and short term data storage, so the computer doesn't have to take the time to access the hard drive to find something. More RAM can contribute to a faster PC. RAM is normally removable by being in slots on the motherboard.
o Basic Input-Output System (BIOS) or Extensible Firmware Interface (EFI) in newer computers
o Buses :
+ PCI bus
+ PCI-E or AGP bus
+ ISA bus (outdated)
+ EISA bus (outdated)
+ USB
* Power supply - a case that holds a transformer, voltage control and fan
* Storage controllers of IDE, SATA, SCSI or other type, that control hard disk, floppy disk, CD-ROM and other drives; the controllers sit directly on the motherboard (on-board) or on expansion cards
* Video display controller that produces the output for the computer display
* Computer bus controllers (parallel, serial, USB, FireWire) to connect the computer to external peripheral devices such as printers or scanners
* Some type of a removable media writer:
o CD - the most common type of removable media, cheap but fragile.
+ CD-ROM Drive
+ CD Writer
o DVD
+ DVD-ROM Drive
+ DVD Writer
+ DVD-RAM Drive
o Floppy disk
o Zip drive
o USB Flash Drive
o Tape drive - mainly for backup and long-term storage
* Internal storage - keeps data inside the computer for later use.
o Hard disk - for medium-term storage of data.
o Disk array controller
* Sound card - translates signals from the system board into analog voltage levels, and has terminals to plug in speakers.
* Networking - to connect the computer to the Internet and/or other computers
o Modem - for dial-up connections
o Network card - for DSL/Cable internet, and/or connecting to other computers.
* Other peripherals

In addition, hardware can include external components of a computer system. The following are either standard or very common.

* Input or Input devices
o Text input devices
+ Keyboard

3-button mouse
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3-button mouse

*
o Pointing devices
+ Mouse
+ Trackball
o Gaming devices
+ Joystick
+ Gamepad
+ Game controller
o Image, Video input devices
+ Image scanner
+ Webcam
o Audio input devices
+ Microphone
* Output or Output devices
o Image, Video output devices
+ Printer
+ Monitor
o Audio output devices
+ Speakers
+ headset