  Image Compression has become an absolute necessity in today's day and age.
With the advent of the Internet era, compressing files to share among other
users is quintessential. Several efforts have been made to reduce file sizes
while still maintain image quality in order to transmit files even on limited
bandwidth connections. This paper discusses the need for Discrete Cosine
Transform or DCT in the compression of images in Joint Photographic Experts
Group or JPEG file format. Via an intensive literature study, this paper first
introduces DCT and JPEG Compression. The section preceding it discusses how
JPEG compression is implemented by DCT. The last section concludes with further
real world applications of DCT in image processing.
