Gif src with base64 coding after it?

Question

I have been asked to work on a web site and I see links like this. Has anyone seen anything like this before? I am wondering what the base64 code is for:

src="data:image/gif;base64,R0lGODlhAQABAID/AMDAwAAAACH5BAEAAAAALAAAAAABAAEAAAICRAEAOw=="

Answer 1

the hash is the actual contents of the gif encoded with base64

example