This is a Summary Score, which summarizes the results of many individual tests.
What does it summarize?
The quality of content in a website. This includes the use of well written, up-to-date text, metadata and imagery. Although some of these areas may require technical expertise to implement, if the website makes proper use of a Content Management System they should not; ideally everything this tests for can be handled by dedicated content developers.
Why is it important?
Typically content is handled by separate developers to the other Summary Scores. This test aims to look at the aspects of the site affected most by content contributors, as opposed to those typically handled by technical developers (see Technology Summary).
In particular, it is possible to have a technically great website with poor content and vice versa. Good content is invaluable for an effective and successful website.