Data compression is the compacting of info by decreasing the number of bits which are stored or transmitted. Because of this, the compressed info needs less disk space than the initial one, so extra content might be stored on identical amount of space. There're different compression algorithms that work in different ways and with a lot of them just the redundant bits are removed, so once the info is uncompressed, there's no loss of quality. Others erase excessive bits, but uncompressing the data afterwards will result in reduced quality in comparison with the original. Compressing and uncompressing content requires a significant amount of system resources, in particular CPU processing time, so every hosting platform which employs compression in real time must have adequate power to support this feature. An example how information can be compressed is to substitute a binary code such as 111111 with 6x1 i.e. "remembering" the number of sequential 1s or 0s there should be instead of storing the whole code.