Hard Drive - The primary computer storage device, which spins, reads and writes one or more fixed disk platters. The hard drive is what stores all your data. It houses the hard disk, where all your files and folders are physically located. A typical hard drive is only slightly larger than your hand, yet can hold over 100 GB of data. The data is stored on a stack of disks that are mounted inside a solid encasement. These disks spin extremely fast (typically at either 5400 or 7200 RPM) so that data can be accessed immediately from anywhere on the drive.
CPU - Stands for “Central Processing Unit.” This is the pretty much the brain of your computer. It processes everything from basic instructions to complex functions. Any time something needs to be computed, it gets sent to the CPU. Every day, it’s compute this, compute that — you’d think the CPU would need a break after awhile. But no — it just keeps on processing. The CPU can also be referred to simply as the “processor.”
Motherboard - Also known as the mainboard or logic board, this is the main circuit board of your computer. If you ever open your computer up, the biggest piece of silicon you see is the motherboard. This is where you’ll find the CPU, the ROM, memory expansion slots, PCI slots, serial ports, USB ports, and all the controllers for things like the hard drive, DVD drive, keyboard, and mouse. Basically, the motherboard is what makes everything in your computer work together. Each motherboard has a collection of chips and controllers that is known as the “chipset”.
Power Supply – An electrical system that converts AC current from the wall outlet into the DC currents required by the computer circuitry.
PCI -Stands for “Peripheral Component Interconnect.” It is a hardware bus designed by Intel and used in both PCs and Macs. Most add-on cards such as SCSI, Firewire, and USB controllers, use a PCI connection.
PCI Express – First came PCI, then PCI-X, then PCI Express. PCI Express can be abbreviated as PCIe or, less commonly and more confusingly, PCX. Unlike earlier PCI standards, PCI Express does not use a parallel bus structure, but instead is a network of serial connections controlled by a hub on the computer’s motherboard. This enables PCI Express cards to run significantly faster than previous PCI cards. Because the PCI Express interface is a serial connection, it does not have a speed measured in Megahertz, like PCI or PCI-X. Instead, its performance is measured in data throughput speeds, which are several times faster than PCI-X. Since PCI Express connections can support such fast data transfer rates, they can be used to connect high-speed devices such as Gigabit Ethernet cards and high-end video cards. For this reason, PCI Express is expected to replace both PCI and AGP connections.
USB – Stands for “Universal Serial Bus.” USB is the most common type of computer port used in today’s computers. It can be used to connect keyboards, mice, game controllers, printers, scanners, digital cameras, and removable media drives, just to name a few. USB is also faster than older ports, such as serial and parallel ports. The USB 1.1 specification supports data transfer rates of up to 12Mb/sec and USB 2.0 has a maximum transfer rate of 480 Mbps.
Firewire – A computer firewall limits the data that can pass through it and protects a networked server or client machine from damage by unauthorized users. Firewalls can be either hardware or software-based.
IEEE-1394 - Stands for the “Institute of Electrical and Electronics Engineers.” This is a non-profit organization that develops, defines, and reviews electronics and computer science standards. Some examples of commonly-used products standardized by the organization are the IEEE 1284 interface (a.k.a. Parallel Port), which many printers use, and the IEEE 1394 interface (a.k.a. Firewire), which is a super-fast connection for digital video cameras, hard drives, and other peripherals.
LCD -Stands for “Liquid Crystal Display.” LCDs are super-thin displays that are used in laptop computer screens and flat panel monitors. Smaller LCDs are used in handheld TVs, PDAs, and portable video game devices. The image on an LCD screen is created by sandwiching an electrically reactive substance between two electrodes. This color of this substance can be changed by increasing or reducing the electrical current. Since LCD screens are based on the principle of blocking light (rather than emitting it), they use up much less power than standard CRT (Cathode-Ray Tube) monitors.
Plasma (in relation to screens) – A plasma display is a computer video display in which each pixel on the screen is illuminated by a tiny bit of plasma or charged gas, somewhat like a tiny neon light. Plasma displays are thinner than cathode ray tube (CRT) displays and brighter than liquid crystal displays (LCD). Also called “gas discharge display,” a flat-screen technology that uses tiny cells lined with phosphor that are full of inert ionized gas (typically a mix of xenon and neon). Three cells make up one pixel (one cell has red phosphor, one green, one blue). The cells are sandwiched between x- and y-axis panels, and a cell is selected by charging the appropriate x and y electrodes. The charge causes the gas in the cell to emit ultraviolet light, which causes the phosphor to emit color. The amount of charge determines the intensity, and the combination of the different intensities of red, green and blue produce all the colors required. consumes more cucrent.
HDMI – Stands for “High-Definition Multimedia Interface.” HDMI is a digital interface for transmitting audio and video data in a single cable. It is supported by most HDTVs and related components, such as DVD and Blu-ray players, cable boxes, and video game systems. While other types of A/V connections require separate cables for audio and video data, HDMI carries the audio and video streams together, greatly eliminating cable clutter. For example, a component cable connection requires three cables for video and two for audio, totaling five cables in all. The same information can be transmitted using one HDMI cable. Because HDMI is a digital connection, HDMI cables are less prone to interference and signal noise than analog cables. Also, since most components, such as DVD players and digital cable boxes process information digitally, using HDMI eliminates the analog to digital conversion other interfaces require. Therefore, HDMI often produces the best quality picture and sound compared to other types of connections.
RAM - Stands for “Random Access Memory,” and is pronounced like the male sheep. RAM is made up of small memory chips that are connected to the motherboard of your computer. Every time you open a program, it gets loaded from the hard drive into the RAM. This is because reading data from the RAM is much faster than reading data from the hard drive.
Running programs from the RAM of the computer allows them to function without any lag time. The more RAM your computer has, the more data can be loaded from the hard drive into the RAM, which can help speed up your computer. In fact, adding RAM can be more beneficial to your computer’s performance than upgrading the CPU.
Flash Memory – Flash memory is a type of electrically erasable programmable read-only memory (EEPROM). The name comes from how the memory is designed — a section of memory cells can be erased in a single action or in a “flash.” A common use of flash memory is to store the BIOS settings in a computer’s ROM. When the BIOS needs to be changed, the flash memory can be written in blocks, rather than bytes, making it easy to update. Most modems use flash memory for the same reason.
AGP – Stands for “Accelerated Graphics Port.” This is a graphics card expansion port designed by Intel that resides on the motherboard of a computer. PCI graphics ports typically run at 33 MHz and have a maximum transfer rate of 132 MB/sec. AGP ports, on the other hand, run at 66 MHz and can transfer data up to 528 MB/sec. This allows games and applications to store and retrieve larger, more realistic 3D shapes and textures without slowing down the animation on the screen. Additionally, AGP cards can store graphics in system memory rather than video memory, which also helps improve performance. Becuase of these advantages, AGP cards will typically have better performance per MB of VRAM than PCI graphics cards.
DVD – Stands for “Digital Versatile Disc.” It can also stand for “Digital Video Disc,” but with the mulitple uses of DVDs, the term “Digital Versatile Disc” is more correct. A DVD is a high-capacity optical disc that looks like a CD, but can store much more information. While a CD can store 650 to 700 MB of data, a single-layer, single-sided DVD can store 4.7 GB of data. This enables massive computer applications and full-length movies to be stored on a single DVD.
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