Summary

Compression is vital in computer science to reduce file sizes, saving storage space and enabling faster internet transmission rates due to less bandwith being used during transmission of a file. When files are large, compression becomes necessary.

There are two main types of compression: lossy and lossless. Lossy compression sacrifices some data to achieve higher compression rates. While it greatly reduces file size, it may lead to quality loss, especially in graphics and audio files.

Lossless compression maintains all original data, ensuring no quality loss during compression. However, it typically achieves lower compression rates compared to lossy compression.

In graphics files, lossy compression might cause image degradation, while lossless preserves the original quality. 

Compression reduces file size, improving internet transmission rates and balancing between quality and file size based on the chosen compression method.