Overclocking can be defined as making your computer go faster than stock speeds at which it was running at. You can overcloack various components in your p.c. The main components that people overclock mainly would have to be the CPU , Graphics Card and memory.
Now why do people overcloack.
People overclock to make there computers run faster which intern runs programs better.
Other people overclock to do benchmarks. These are test to show how fast your P.C is. These people compete to see who has the fastest P.C in the world.
If you do decide to overclock be careful because you could seriously damage your computer.