System Unit

Expansion Card

Expansion Card is also called as an add-on card, internal card or interface adapter, an expansion card is an electronic board or card added in a desktop computer or other non-portable computer to give that computer a new ability. It has the ability to connect to another computer using a network cable. Below is a list of expansion cards that could be installed in a an available expansion slot in all computers.
Interface card (ATA / Bluetooth / EIDE / IDE / Parallel / RISC / SCSI /Serial / USB)

Modem
MPEG Decoder
Network Card
Sound Card
Video Card
Video capture card
Note: Although each of the above devices are available as expansion cards, it is important to realize that they can also be on the motherboard.

Network Interface

The word for Network Interface Card is also known as NIC. It is also commonly referred to as a network adapter and is an expansion card that enables a computer to connect to a network such as a home network or the Internet using a Ethernet cable. The basic graphic example will be the SMC EZ Card 10/100 PCI network card, a type of network card commonly found in most desktop computers today that do not already have an integrated network on their motherboard.
The second bottom image on the right is another example of a network card, a PC Card SMC EZ Card 10/100 wireless network card. These types of cards are used in laptop computers that do not have a built-in wireless network.

Cache Memory

Cache Memory can be also pronounced as Cash. Cache is a high-speed access area that can be either a reserved section of main memory or a storage device. The two main types of cache are: memory cache and disk cache. Memory cache is a portion on memory of high-speed static RAM (SRAM) and is effective because most programs access the same data or instructions over and over. By keeping as much of this information as possible in SRAM, the computer avoids accessing the slower DRAM.
Just like memory caching, disk caching is used to access commonly accessed data but instead of using high-speed SRAM, a disk cache uses conventional main memory. The most recently accessed data from the disk is stored in a memory buffer. When a program needs to access data from the disk, it first checks the disk cache to see if the data is there.
Most computers today come with L3 cache and/or L2 cache, while older computers included only L1 cache. Disk caching can dramatically improve the performance of applications because accessing a byte of data in RAM can be thousands of times faster than accessing a byte on a hard disk.

Plug and Play

Short for Plug and Play, PnP is an ability of a computer to detect and configure a new piece of hardware automatically, without the requirement of the user to physically configure the hardware device with jumpers or dipswitches. Plug and Play was introduced on IBM compatible computers with the release of Microsoft Windows 95, where Apple Macintosh computers have always supported the ability to automatically detect and install hardware.
For Plug and Play to operate properly on IBM compatible computers the user must have the following:
BIOS supporting Plug and Play.
Windows 95, 98, 2000 or other operating systems supporting PnP.
Peripheral with PnP support.
Today, all new computers have PnP capabilities.

Computer Chips

Integrated circuit or small wafer of semiconductor material embedded with integrated circuitry. Chips comprise the processing and memory units of the modern digital computer (see microprocessor; RAM). Chip making is extremely precise and is usually done in a “clean room,” since even microscopic contamination could render the chip defective. As transistor components have shrunk, the number per chip has doubled about every 18 months (a phenomenon known as Moore's law), from a few thousand in 1971 (Intel Cord's first chip) to millions by 1989. Nanotechnology is expected to make transistors even smaller and chips correspondingly more powerful in the 21st century.

Slots

A type of computer processor connection designed to make upgrading the processor much easier, where the user would only have to slide a processor into a slot. The original slot, or slot 1, was first released by the Intel Corporation. Later, AMD released another type of slot known as the Slot A. Both slots look similar but are not compatible. Later, Intel released the slot 2, which was a bigger slot used with the later versions of the Pentium II processors. Today, slot processors are no longer found in new computers.

Serial Port


Serial port on the computer used to connect a serial device to the computer and capable of transmitting one bit at a time. Serial ports are typically identified on IBM compatible computers as COM (communications) ports. For example, a mouse might be connected to COM1 and a modem to COM2. With the introduction of USB, FireWire, and other faster solutions serial ports are rarely used when compared to how often they've been used in the past. To the right is a close up of a serial port on the back of a computer.

Below is a listing of various hardware components that can be purchased and used with your serial port.


Mouse - One of the most commonly used devices for all computers except laptop(if needed).
Modem - It is another commonly used device for serial ports. Used commonly with older computers, however, is also commonly used for its ease of use.
Network - One of the common uses of the serial port, which allowed two computers to connect together. On the same time, it allow large files to be transferred between the two.
Printer - Today, this is not a commonly used device for serial ports. However, was frequently used with older printers and plotters.




Parallel Port


Parallel Port canreferred to as the Centronics interface or Centronics connector. Just after the company that originally designed it, the port was later pass down by Epson. The parallel port is found on the back of IBM compatible computers and is a 25-pin (type DB-25) computer interface commonly used to connect printers to the computer. It is used to connect to the printer in a way to initialize with the computer.

Universal Serial Bus

Short for Universal Serial Bus, USB is a standard that was introduced in 1995 by Intel, Compaq, Microsoft and several other computer companies. USB 1.x is an external bus standard that supports data transfer rates of 12 Mbps and is capable of supporting up to 127 peripheral devices. The image to the right is an example of a USB device, the SMC EZ Connect Wireless Bluetooth adapter adds Bluetooth connectivity for your computer.
USB 2.0, also known as "hi-speed USB", was developed by Compaq, Hewlett Packard, Intel, Lucent, Microsoft, NEC and Philips and was introduced in 2001. Hi-speed USB is capable of supporting a transfer rate of up to 480 Mbps and is backwards compatible, meaning it is capable of supporting USB 1.0 and 1.1 devices and cables.

Firewire Port

Firewire is also known as IEEE-1394. FireWire was developed by Apple in 1995 and is a bus that has a bandwidth of 400-800 Mbps, can handle up to 63 units on the same bus, and is hot swappable. Meaning, it can be plug into it with any cable with same sizes. Users more familiar with USB can relate FireWire to USB as it has a lot of the same similarities. Just like USB, FireWire has dozens of different devices such as removable drives and cameras that can be connected to it.