SDRAM Definition Stands for "Synchronous Dynamic Random Access Memory." Yeah, it's a mouthful, but if you memorize it, you can really impress your friends. SDRAM is an improvement to standard DRAM because it retrieves data alternately between two sets of memory. This eliminates the delay caused when one bank of memory addresses is shut down while another is prepared for reading. It is called "Synchronous" DRAM because the memory is synchronized with the clock speed that the computer's CPU bus s...

DDR Definition Stands for "Double Data Rate." It is an advanced version of SDRAM, a type of computer memory. DDR-SDRAM, sometimes called "SDRAM II," can transfer data twice as fast as regular SDRAM chips. This is because DDR memory can send and receive signals twice per clock cycle. The efficient operation of DDR-SDRAM makes the memory great for notebook computers since it uses up less power.

DDR4 Definition Stands for "Double Data Rate 4." DDR4 is the fourth generation of DDR RAM, a type of memory commonly used in desktop and laptop computers. It was introduced in 2014, though it did not gain widespread adoption until 2016. DDR4 is designed to replace DDR3, the previous DDR standard. Advantages include faster data transfer rates and larger capacities, thanks to greater memory density and more memory banks (16 rather than 8). DDR4 also operates at a lower voltage (1.2V compared to 1...

Desktop Computer Definition A desktop computer (or desktop PC) is a computer that is designed to stay in a single location. It may be a tower (also known as a system unit) or an all-in-one machine, such as an iMac. Unlike laptops and other portable devices, desktop computers cannot be powered from an internal battery and therefore must remain connected to a wall outlet. In the early age of computers, desktop computers were the only personal computers available. Since laptops and tablets did not...

Mainframe Definition A mainframe is an ultra high-performance computer made for high-volume, processor-intensive computing. They are typically used by large businesses and for scientific purposes. You probably won't find a mainframe in any household. In the hierarchy of computers, mainframes are right below supercomputers, the most powerful computers in the world. (Which is why they are aptly named "supercomputers.") Yet a mainframe can usually execute many programs simultaneously at a high spee...

System Requirements Definition Whenever you purchase software or hardware for your computer, you should first make sure your computer supports the system requirements. These are the necessary specifications your computer must have in order to use the software or hardware. For example, a computer game may require you computer to have Windows XP or later, a 2.0 GHz processor, 512 MB or RAM, a 64 MB graphics card, and 500 MB or hard drive space. If your computer does not meet all of these requireme...

Peripheral Definition A computer peripheral is any external device that provides input and output for the computer. For example, a keyboard and mouse are input peripherals, while a monitor and printer are output peripherals. Computer peripherals, or peripheral devices, are sometimes called "I/O devices" because they provide input and output for the computer. Some peripherals, such as external hard drives, provide both input and output for the computer. For an extended list of various peripheral...

PCI Definition Stands for "Peripheral Component Interconnect." PCI is a hardware bus used for adding internal components to a desktop computer. For example, a PCI card can be inserted into a PCI slot on a motherboard, providing additional I/O ports on the back of a computer. The PCI architecture, also known as "conventional PCI," was designed by Intel and introduced in 1992. Many desktop PCs from the early 1990s to the mid 2000s had room for two to five PCI cards. Each card required an open slo...

System Unit Definition The system unit, also known as a "tower" or "chassis," is the main part of a desktop computer. It includes the motherboard, CPU, RAM, and other components. The system unit also includes the case that houses the internal components of the computer. The term "system unit" is often used to differentiate between the computer and peripheral devices, such as the monitor, keyboard, and mouse. For example, if a repair shop asks you to bring in your computer, it may be unclear whe...

NIC Definition Stands for "Network Interface Card" and is pronounced "nick." A NIC is a component that provides networking capabilities for a computer. It may enable a wired connection (such as Ethernet) or a wireless connection (such as Wi-Fi) to a local area network. NICs were commonly included in desktop computers in the 1990s and early 2000s. In the 1980s and early 1990s, many computers did not include networking capabilities, so a NIC could be added as an expansion card. Most NICs were ins...