Computer Processor

A central processing unit (CPU) is an electronic circuit that can execute computer programs. This broad definition can easily be applied to many early computers that existed long before the term "CPU" ever came into widespread usage. The term itself and its initialism have been in use in the computer industry at least since the early 1960s (Weik 1961). The form, design and implementation of CPUs have changed dramatically since the earliest examples, but their fundamental operation has remained much the same.
Early CPUs were custom-designed as a part of a larger, sometimes one-of-a-kind, computer. However, this costly method of designing custom CPUs for a particular application has largely given way to the development of mass-produced processors that are suited for one or many purposes. This standardization trend generally began in the era of discrete transistor mainframes and minicomputers and has rapidly accelerated with the popularization of the integrated circuit (IC). The IC has allowed increasingly complex CPUs to be designed and manufactured to tolerances on the order of nanometers. Both the miniaturization and standardization of CPUs have increased the presence of these digital devices in modern life far beyond the limited application of dedicated computing machines. Modern microprocessors appear in everything from automobiles to cell phones to children's toys.
Abbreviation for central processing unit, and pronounced as separate letters. The CPU is the brains of the computer. Sometimes referred to simply as the central processor,but more commonly called processor, the CPU is where most calculations take place. In terms of computing power, the CPU is the most important element of a computer system.
On large machines, CPUs require one or more printed circuit boards. On personal computers and small workstations, the CPU is housed in a single chip called a microprocessor. Since the 1970's the microprocessor class of CPUs has almost completely overtaken all other CPU implementations.
The CPU itself is an internal component of the computer. Modern CPUs are small and square and contain multiple metallic connectors or pins on the underside. The CPU is inserted directly into a CPU socket, pin side down, on the motherboard. Each motherboard will support only a specific type or range of CPU so you must check the motherboard manufacturer's specifications before attempting to replace or upgrade a CPU. Modern CPUs also have an attached heat sink and small fan that go directly on top of the CPU to help dissipate heat.
Two typical components of a CPU are the following:
The arithmetic logic unit (ALU), which performs arithmetic and logical operations.
The control unit (CU), which extracts instructions from memory and decodes and executes them, calling on the ALU when necessary.
The Central Processing Unit (CPU) is responsible for interpreting and executing most of the commands from the computer's hardware and software. It is often called the "brains" of the computer.
The CPU is also known as processor, microprocessor, central processor, “the brains of the computer.
If you’re in the market for a new computer, it’s necessary to understand the function of a CPU. Also known as the Central Processing Unit or processor, the CPU is essentially the “brains” of your computer. Without the CPU, you wouldn’t be able to play games, type research papers, or surf the Internet. Your computer would basically be a very expensive paperweight.
Sometimes people mistakenly believe the case or chassis of a computer is the CPU. However, a CPU is an internal component of the computer. You can’t see it from the outside of the system; you’d have to peek inside and remove both the CPU heatsink and fan to get a good look.
The first CPUs were used in the early 1960s. They were custom designed as part of a larger computer, making them prohibitively expensive. Once engineers figured out how to mass produce the CPU, personal computers became more affordable for the average American. With the introduction of the integrated circuit in the late 1970s, it became possible for smaller CPUs to be manufactured as well. This helped transform computers from large, bulky devices that took up entire rooms to more manageable desktop and laptop models.
Today, Intel is the best-known manufacturer of computer CPUs. No matter what type of computer you have, however, your CPU works by executing a series of stored instructions known as a program. Most CPUs conform to the von Neumann architecture, which says that the CPU must fetch, decode, execute, and writeback the data in a fairly rapid succession.
Since the CPU is one of the most important parts of a computer, it should come as no surprise that it is also the most expensive. In fact, if your computer is more than three years old and your CPU has been damaged by static electricity or some other factor, you may want to consider upgrading to an entirely new computer. A newer, faster CPU will often provide enough additional computing power to make the purchase a wise investment.
CPUs are sometimes called microprocessors, although these two terms are not quite interchangeable. The microprocessor, first introduced in the 1970s, reduces the word size of a CPU from 32 bits to 4 bits in an attempt to allow the transistors of the logic circuits to fit on a single part. Often, it takes more than one microprocessor to perform all of the functions of a CPU. Microprocessors are also commonly used in cell phones, automobiles, and children’s electronic toys.
So what is the processor? Well in the simplest of terms, it’s your computers brain. The processor tells your computer what to do and when to do it, it decides which tasks are more important and prioritizes them to your computers needs.
There is and has been many processors on the market, running at many different speeds. The speed is measured in Megahertz or MHz. A single MHz is a calculation of 1 million cycles per second (or computer instructions), so if you have a processor running at 2000 MHz, then your computer is running at 2000,000,000 cycles per second, which in more basic terms is the amount of instructions your computer can carry out. Another important abbreviation is Gigahertz or GHz. A single GHz or 1 GHz is the same as 1000 MHz . Sounds a bit confusing, so here is a simple conversion :
1000 MHz (Megahertz) = 1GHz (Gigahertz) = 1000,000,000 Cycles per second (or computer instructions).
Now you can see why they abbreviate it, could you imagine going to a PC store and asking for a one thousand million cycle PC please. A bit of a mouth full isn’t it?
So when buying a new computer always look for fastest you can afford. The fastest on the market at the time of writing this article is 3.8 GHz (3800 MHz). Remember though that it is not necessary to purchase such a fast processor, balance your needs, do you really need top of the range? Especially when the difference say between a 3.5 GHz (3500 MHz) and a 3.8 GHz (3800 MHz) processor will be barely noticed (if noticed at all) by you, while the price difference is around £100. With the money you save you could get a nice printer and scanner package.
Now that we have covered the speeds, there is one more important subject to cover. Which processor? There are 3 competitors at present, the AMD Athlon, Intel Pentium and the Intel Celeron. They come in many guises, but basically the more cores they have and the higher the speed means better and faster.
Processors now come as dual core, triple core and quad core. These processors are the equivalent of running two cpu's (Dual core), three CPU's ( Triple core) or four (Quad core).
In the past Intel Pentium the best and most expensive of them all, and remains today one of the most popular on the market. In layman’s terms it is/was the designer processor, although AMD have some superb if not better releases and equally highly priced and advanced products. It would be hard to say which is best as they are direct competitors.
Lastly there is the Intel Celeron; this processor is a budget version of the Intel Pentium 4, the processor you find in most budget computers. If the purse is tight, and you need a computer, then this is your port of call. You will find many sub £400 computers fitted with this processor.

References

Amdahl, G. M., Blaauw, G. A., & Brooks, F. P. Jr. (1964). Architecture of the IBM System/360,
IBM Research.

Brown, Jeffery (2005). "Application-customized CPU design". IBM developerWorks.
http://www-128.ibm.com/developerworks/power/library/pa-fpfxbox/?ca=dgr-
lnxw07XBoxDesign. Retrieved on 2005-12-17.

http://en.wikipedia.org/wiki/CPU

http://www.webopedia.com/TERM/C/CPU.html

http://pcsupport.about.com/od/componentprofiles/p/p_cpu.htm

http://www.wisegeek.com/what-is-a-cpu.htm

http://www.hardware.windowsreinstall.com/processor.htm