As the name suggests (blog is short for weblog), a blog is an electronic, public journal. The ease with which they are created and maintained has led to a proliferation of blogs on nearly every subject. A common feature of these sites is their interactivity; many bloggers encourage readers to comment on - that is, to post public responses to - their entries. The provided links explain blogs in greater depth and list some notable blogs on a variety of subjects.

Introduction to Blogging

An easy-to-read discussion of what blogs are, what they can be used for, and why you should be interested in them. From BlogBasics.com.

Wikipedia entry on blogs

A detailed discussion of blogs, including their history and influence in contemporary media and journalism.

Blogs 101

A selection of popular and interesting blogs, as chosen by The New York Times.

Technorati

An exhaustive blog repository, featuring a searchable database and a Top 100 list.

Some thoughts on classroom blogging

• Integrating, Evaluating, and Managing (Prof Hacker)
• Lessons from a First-Time Course Blogger (cac.ophony)
• Pedagogy and the Class Blog (Sample Reality)
• Hub-and-spoke blogging with lots of students (Teleogistic)