The paragraph is followed by an incomplete phrase or sentence which summarizes the main idea of the paragraph. Choose the missing words of the phrase or sentence.

This new kind of website is known as a“ weblog ”,or “ bolg ”.A weblog is an online journal, typically consisting of a personal diary or social and political commentary ,sometimes with replies from readers. Blogs have common elements:updated frequently(usually daily); informal; grouped by date with links to archives of older posts.
The passage talks about（）