U1: Hardware and Software Principles

Things the user will need the computer to be able to do.

• The different parts and capabilities of the computer • User requirements dictate the specifications of a computer

Hardware components of a computer

An inch by inch silicon chip including millions of transistors allowing the computer to compute.

Series of platters/disks storing programs and files

• When running a program, programs are copied to RAM then run from the RAM • When turning a computer off, the RAM is wiped clean

• Regular computer user can’t write to ROM. • Stores data and instructions for when the computer boots up.

• Main circuit board all internal components attach to. • Holds connections that allow parts to communicate.

• Extra components enhancing audio performance. • Allows for amplified audio or to plug a guitar into a computer.

• Extra components enhancing video performance. • Makes graphics render smoother.

• The no. per second the processor can turn a signal on and off again • How fast a processor processes information or performs operations

• Hertz → Hz → 1 time/second • Megahertz → MHz → 1 million/second • Gigahertz → GHz → 1 billion/second

Multi-core CPU can focus on multiple tasks

• Most important spec for memory is capacity • Smallest unit of memory is a bit (1 or 0) • One letter needs at least one byte (8 bits) • Byte is the measurement unit used

• 1 KB = 1,024 bytes = half typed page • 1 MB = 1,024 KB = 500 typed pages • 1 GB = 1,024 MB = 400 images • 1 TB = 1,024 GB = 17,000 hours of music

• External hardware device of a computer • Purchased peripherals influenced by needs of the user

Devices where data goes from the device into the computer

• Devices where data goes from computer to the device. • Touchscreen monitors would be considered input and output devices

• More expensive toner that lasts longer • Lower cost for black-and-white per page; higher initial cost • Excellent quality for text and monochrome

• Higher cost for colour and black/white per page • Better quality for colour and photo printing • Frequent, cheaper cartridge replacement

• Liquid crystals sandwiched between glass panels • Lower brightness than LEDs; less energy efficient • Good colour accuracy; thick monitor

• Flash memory; faster speeds • Durable; silent; higher cost

• Uses LED backlighting instead of CCFLs • Higher brightness; energy efficient • Better color accuracy; thinner

• Spinning magnetic disks; slower • Vulnerable; noisy; lower cost