The Processor or CPU is the "brain" of the computer. The more powerful processor your computer has, the faster it will work. The Processor is sometimes called "the chip".
The Processor is often labelled by the number of "cores" (separate 'brains' which can work in parallel).
Processors are made by two companies: Intel and AMD. They are both equally good.
The speed of both types of processor are measured in Gigahertz (GHz). The higher the speed, the faster the processor.
The current Intel processors are called i3, i5 and i7.
Most standard computers will come with an i3 processor. High performance computers will have an i5 processor. If you need a very powerful computer, then the i7 processor could be the correct one for you.
These processor types have been around for several years: Intel has produced many new versions of each type.
Servers tend to use Intel Xeon processors.
The common current AMD processors are called Opteron and come with 1, 2, 4, 6, 8, 12 or 16 cores.
x2 (dual-core) is for standard computers
x4 (quad-core) or better for high performance computers