AO1

Overview of Computer Concepts

• Most network-related devices involve the use of a computer. Specialized computers are used to transfer data between computers and networks. Some common operating systems include Windows, Linux, UNIX, and MAC OS.

• When computers are produced by companies, they come installed with a system called BIOS (Basic Input Output System). Sellers or dealers then install an operating system, and users need to install application software.

• Computer systems consist of three components: input, processing, and output. Input involves the user typing on a keyboard, processing is done by the computer's CPU, and output is displayed on a monitor.

• Components of a computer include input devices like keyboards and mice, processing components like CPUs and RAM, and output devices like monitors and printers. CPUs nowadays have multiple processors called cores.

• There are two main categories of storage: short-term and long-term. Short-term storage is provided by RAM, which is crucial for a computer's efficient operation. Virtual memory can also be used to store less frequently used data. Long-term storage includes hard disks, CDs/DVDs, and USB flash drives, which are used to store documents and multimedia files.

• Major components of a personal computer include the motherboard, hard drive, RAM, and BIOS/CMOS. The motherboard consists of various components such as CPU sockets, expansion slots, RAM slots, and connectors for storage devices.

• Computer buses are collections of wires that carry signals between different parts of the computer. They connect the CPU to RAM, disk drives, and expansion slots. Data buses carry data signals, address buses carry address signals, and control buses carry control signals.

• I/O polling and interrupt are two ways to handle events generated by input devices when the CPU is busy. They allow the CPU to stop the current work and respond to more important tasks.

• Solid State Drives (SSDs) are used instead of hard drives due to their speed and reliability. They use flash memory but are more expensive.

• BIOS is a set of instructions located in a chip on the motherboard that tells the CPU to perform certain tasks when the power is first applied to the computer. It also performs a power-on self-test (POST). CMOS is a type of memory that stores hardware configuration settings.

• The computer boot procedure involves supplying power to the motherboard, the CPU starting, the CPU carrying out the BIOS setup routine (including POST), searching for an operating system on boot devices, and starting OS services.

• Network communication involves connecting two or more computers using a transmission medium like cables or airwaves. A computer needs a Network Interface Card (NIC) to connect to a network. NICs contain MAC addresses.

• Wireless NICs need to be chosen based on the type of wireless Access Point (AP) being used. They connect to networks using a service set identifier (SSID), which is the name assigned to the wireless network.

• There are different types of computers, including embedded computers, personal computers, servers and enterprise systems, supercomputers and grid computers, and "cloud" computing