Egg protein is either derived from whole eggs or egg whites depending on the source. The whole egg version has cholesterol and fat, which makes it undesirable for many bodybuilders trying to stay away from these elements, but it also tends to taste more rich. Egg white protein is a much cleaner form, but it tends to cost a bit more and have a much more bland taste. Egg protein is a good source of protein for many bodybuilders and the old school guys will swear by egg as their favorite protein source. It is a complete protein that has a slightly lower biological value vs. whey but it is still a great protein source for building muscle. Egg protein tends to taste good in general, but it can have a sulphuric effect for many bodybuilders (i.e. smelly gas), which makes it unpleasant for many people.