Edexcel curriculum (2015)
Inside the CPU
LAN, WAN and PAN
The world wide web
HTML and CSS
Inside the CPU are various areas that carry out various functions
Program counter (PC) - an incrementing counter that keeps track of the memory address of the instruction that is to be executed next or in other words, holds the address of the instruction to be executed next.
Memory address register (MAR) - holds the address of a memory location of which data/instruction is to be fetched/written
Memory data register (MDR) - a two-way register that holds data fetched from memory (and ready for the CPU to process) or data waiting to be stored in memory. (This is also known as the memory buffer register (MBR).)
Instruction register (CIR) - a temporary holding ground for the instruction that has just been fetched from memory.
Control unit (CU) - decodes the program instruction in the IR, selecting machine resources such as a data source register and a particular arithmetic operation, and coordinates activation of those resources.
Arithmetic logic unit (ALU) - performs mathematical and logical operations.
Buses are the connective wiring found in the motherboard.
Transfers binary data from place to place
Sends and receives signals that control the CPU and other components
Carries the binary address of memory locations