Most annotations both summarize and evaluate. Be sure to check with your professor to know what she or he wants in your annotations.
A summary describes the source by answering who wrote the document and what their overall argument is. You don't need to include every part of their argument; just the parts that are relevant to your topic.
An evaluation critically assesses the work for accuracy, relevance, and quality. Check for any biases, holes, or particular strengths in their argument. Use the CRAAP Test to evaluate your source!
London, Herbert. “Five Myths of the Television Age.” Television Quarterly, vol. 10, no. 1, Mar. 1982, pp. 81-89.
Herbert London, the Dean of Journalism at New York University and author of several books and articles, explains how television contradicts five commonly believed ideas. He uses specific examples of events seen on television, such as the assassination of John Kennedy, to illustrate his points. His examples have been selected to contradict such truisms as: “seeing is believing”; “a picture is worth a thousand words”; and “satisfaction is its own reward.” London uses logical arguments to support his ideas which are his personal opinion. He does not refer to any previous works on the topic. London’s style and vocabulary would make the article of interest to any reader. The article clearly illustrates London’s points, but does not explore their implications leaving the reader with many unanswered questions.
"How to Write Annotated Bibliographies." Memorial University Libraries, www.library.mun.ca/researchtools/guides/writing/annotated_bibl/. Accessed 29 June 2016.