Entity Framework POCO and Self Tracking entities

Hel开发者_StackOverflow中文版lo I wonder what's the difference between standard EF objects, POCO and Self Tracking Entities. I was looking the web but couldn't find a valuable introduction. Any help would be appreciated.

POCO is plain class with only mapped fields. STE is very similar but in advance it contains logic implemented to each property and some collections which are used to tracking changes made to entity.