An annotation is more than just a brief summary of an article, book, website or other type of publication. An annotation should give enough information to make a reader decide whether to read the complete work. In other words, if the reader were exploring the same topic as you, is this material useful and if so, why?
While an abstract also summarizes an article, book, website or other type of publication, it is purely descriptive. An annotation will not only describe the source, but also explain how that source supports your thesis.
An annotated bibliography is an organized list of sources (like a reference list). It differs from a straightforward bibliography in that each reference is followed by a paragraph length annotation, usually 150–200 words in length.
A descriptive or informative annotated bibliography describes or summarizes a source, including why the source is useful for researching a particular topic or question.
For example:
Breeding evil. (2005, August 6). Economist, 376(8438), 9. Retrieved from http://www.economist.com
This editorial from the Economist describes the controversy surrounding video games and the effect they have on people who use them. The author points out that skepticism of new media have gone back to the time of the ancient Greeks, so this controversy surrounding video games is nothing new. The article also points out that most critics of gaming are people over 40 and it is an issue of generations not understanding one another, rather than of the games themselves. As the youth of today grow older, the controversy will die out, according to the author. The author of this article stresses the age factor over violence as the real reason for opposition to video games and stresses the good gaming has done in most areas of human life. This article is distinctive in exploring the controversy surrounding video games from a generational standpoint and is written for a general audience.
Now you are ready to begin writing your own annotated bibliography.