CPU stands for "Central Processing Unit". It can be thought of as the brain of the computer. In the first personal computers the CPU carried out all the processing. In more modern computers the CPU delegates specialised processes - like graphics handling - to other processors. In the most powerful computers there are more than one CPUs. Super computers can have more than 100,000 CPUs.
The CPU is also called the microprocessor or just the processor. Intel or Advanced Micro Devices produces most CPUs. Only recently were high-powered computers able to have multi-core CPUs. There are dual-core CPUs, which contain two cores; there are also quad-core CPUs, which contain four cores. There are many benefits to Multi-core CPUs. To start, they are helping to speed up the processing of a computer while decreasing the heat production. Multi-core CPUs are also responsible for multitasking, such as burning a cd while browsing the Internet.
The CPU also consist of a variety of connections and components that are confined together and connected directly to the motherboard. A motherboard provides the electrical connections by which the other components of the system communicate. It also connects the central processing unit and hosts other subsystems and devices. The motherboard is The main circuit board of a computer, located inside the system unit, to which all computer system components connect. ( Understanding Computers 13th edition). Today most personal computers use central processing units (CPU's) manufactured by Inter or Advanced Micro Devices (AMD). CPU manufacturers include creating CPU's that are as energy efficient as possible, because that would reduce power consumption and increase the battery life of the computer. Core i7 (quad-core) and AMD Phenom II ( its available in different -core versions) are most commonly used with desktop computers. Intel Core 2 and AMD Turion X2 mobile processors, both are design specifically for notebook and tablet computers.