Computer Hardware – The Skeleton of a Computer
Computer hardware refers to the physical components that constitute a computer system. It refers to all the physical parts or components of a computer system, such as central processing units, cases, modems, motherboards, video cards, sound cards, and random access memory (RAM). Hardware is physical and can be touched, as opposed to software which is theoretical and exists as an idea, application, symbol, or concept. It is the hardware within a computer that tells it what to do and without hardware, software would cease to function.
Central Processing Unit
A central processing unit (CPU) is the main hardware component of a computer. It is basically a chip that takes instructions from software, makes calculations by performing arithmetic, logical, and operations, and then gives results. Many computers today contain multiple CPUs, which allow for distributed computing.
A computer case, or tower, holds all of the hardware components together. It has plenty of room for all the necessary components, including fans for cooling.
A modem is a hardware device that modulates and demodulates a carrier signal to encode digital information between the digital data of a computer and the analog signal of a telephone line. Information on a computer is stored digitally whereas information transmitted over a telephone line is in analog waves. A modem simply converts between these two wave forms.
A motherboard is the main circuit board of a computer. It contains the connectors for attaching additional boards or hardware. The motherboard typically has a CPU, BIOS, mass storage interfaces, serial and parallel ports, memory, expansion slots, and all the controllers for peripheral devices attached to it.
A video card, also widely known as a graphics card, is hardware which generates a feed of output images to display. In other words, a video card outputs graphics to the monitor for the user to see.
A sound card is similar to a video card. It is also a piece of hardware which generates a feed of output, but its output is sound. It converts digital sounds to real sounds for users to hear. An audio device or speakers are required in order to hear the audio output from the sound card.
RAM is a type of memory found in computers that allows for data to be accessed randomly, without touching or going through the preceding data. There are two types of RAM: dynamic random access memory (DRAM) and static random access memory (SRAM). The main difference between the two types of RAM is speed: DRAM needs to be refreshed more than a thousand times per second and SRAM does not. Since RAM is volatile, it loses its contents or resets when the power of the computer is turned off.