Many times we face a situation when our Ubuntu Netbook becomes pretty slow. And when we check out our RAM, we find that only half of our RAM is used and the SWAP memory usage is gone upto 25% or 50% or even more. Confused??

Swap memory is used as an alternative to RAM. It is a small partition in the hard disk, that is used to give your system extra memory when your RAM is full. However, it is not as efficient as RAM and quite slow.