The Processor

• The CPU is often described as the "brains" of the computer. It is like a Universal Turing machine in that it goes through memory and interprets what it finds there as instructions.

• Almost all CPUs contain a program counter (PC) and one or more registers.

• The program counter contains the memory address of the instruction the CPU is currently interpreting. Unless the instruction is a special "Jump" instruction, the program counter will be incremented when the CPU is done interpreting the current instruction, and the next instruction will be loaded into the CPU.

• These steps of loading what the Program Counter points to, interpreting it, and then incrementing the Program Counter compose what is called the processor cycle.

• Registers are special places where the CPU can store and manipulate data. They are typically located on the CPU chip, and are usually much faster than memory.