The Central Processing Unit is the principal component of all types of computer like server, desktop and laptop. It carries out arithmetic, logical, input and output operations of the computer system. The term was first coined in 1960s.
In the early computer systems of 1950s, programs written for one type of machine could not write on another type. The reason was that there was no upward compatible computer architecture with multiple implementation. In 1960s, IBM came up with a single reference computer system known as System/360 with capabilities that is supported by all machines of the family. In the next decade, Intel introduced 4004 processor on a single printed board amd cpu prices. RISC processors were invented in 1980s. From 1990s and onwards, various concepts like parallel processing, multithreading, intelligent RAM, reconfigurable logic have been implemented on the CPUs. Since CPU became complex in architecture, network support for CPU has become vital.
A processor operates on bits of data in the form of binary digits. It receives data from peripherals or memory, processes that data and then sends the data back to system memory or peripherals. Processors are categorized by the size of the data they process. Generally 16 bit, 32 bit, 64 bit processors are available in the market. As the names indicate, 16 bit processor is designed to operate on 16 bit data, 32 bit processor on 32 bit data and 64 bit processor on 64 bit data. That means 32 bit processor operates two times faster than 16 bit processor and so on.
The speed at which the processor operate on data is defined as Processor Clock Rate. Every processor has its internal clock, which generate pulses at which instructions are executed and all components are synchronized. A fixed number of clock cycles are required by the CPU to execute instructions. Faster clock makes CPU operation faster. CPU, like any other sequential logic devices, is synchronous machine,because it operates on a synchronous signal. Processor clock rate could be increased with service of Computer support providers.
This internal part of microprocessor contains hard coded algorithms which perform floating point calculations. All Intel processors till 80486 featured external floating point units. Pentium was the first Intel processor which was introduced with in built floating point unit.
The sub scalar CPU executes one instruction on one or two units of data at one time. To improve the CPU operation, the method of parallel computing has been invented, which makes the processor do the parallel computation in stead of linear computation. Two methods for achieving parallel computation are Instruction Level Parallelism (ILP) and Thread Level Parallelism (TLP). ILP increases the speed at which instructions are executed, while TLP increases the number of threads that CPU executes simultaneously.