The word blog is a combination of the words "Web" and "Log." The word "blog" has also evolved into a verb, referring to the act of adding or creating content for web logs.
Blogs are as diverse as the internet-using population itself, often providing commentary or analysis of subjects ranging from politics to personal experiences. The interface allows text and images, as well as links to other web sites related to the subject. This facilitates rich presentation of subjects with only a few clicks of the mouse. For example, a commentary on a recent political speech may provide an embedded link to a video of the speech on YouTube, or link to an article about the speech in the New York Times. Blogs also act as online diaries, where bloggers feel comfortable spouting opinions, funny stories, personal problems; a blog serves to help create a person's online identity.
Another important use of blogs more popular today is when underground stores and small businesses feel obligated to use a blog to give information and receive feedback from customers and post links to other stores. Reasons for this are because they either can't pay for a full website and for its updates, or would rather be closer to the community and connect with the customers.
Readers of most blogs are given permission to comment in an interactive computer interface format which is then visible by all subsequent readers. This lends a sense of community to many blogs and promotes the concept of web 2.0.
"In May 2007, blog search engine Technorati was tracking more than 71 million blogs."
- http://justtv.wordpress.com/ Professor Jason Mittell's Blog, "Just TV"
-  http://technorati.com/ "Blogosphere sees healthy growth" (2006-11-08). Retrieved on 2007-5-13. Linked through http://en.wikipedia.org/wiki/Blogs