On a Web site, a blog, a short form for weblog, is a personal journal that is frequently updated and intended for general public consumption. Blogs generally represent the personality of the author or the Web site and its purpose. Topics sometimes include brief philosophical musings, commentary on Internet and other social issues, and links to other sites the author favors. The essential characteristics of the blog are its journal form, typically a new entry each day, and its informal style.

The author of a blog is often referred to as a blogger. People who post new journal entries to their blog may often say they blogged today, they blogged it to their site, or that they still have to blog.