In this paper, the authors are going to throw light on the concept of data compression, i.e. reducing the size of data by removing excess and extra information so that its transfer becomes easier and less bulky. Moreover, they will also discuss some of the data compression techniques and draw a line on their pros and cons as compared to each other. Data compression helps them to reduce data space and increases transmission capacity as well as efficiency. It basically eliminates data redundancy in data which is to be communicated and thus increases efficiency of data density.