How blogs work

     At its simplest, a blog is an online journal where the entries are published with the most recent first. There are a number of features that make blogs noteworthy and different to other websites:
     Tone: blogs tend to be written in a personal, conversational style. They are usually the work of an identified author or group of authors.
     Topic: blogs tend to define what it is they are writing about. They can be as specific as a blog about a book in progress or as wide in scope as “my musings on life and stuff”.
     Links and trackbacks: the services people use to write blogs make it very easy for them to insert links to other websites, usually in reference to an article or blog post or to provide further information about the subject they are writing about.
     Comments: each blog post has a comments section, effectively a message board for that article. On blogs with large audiences the debates in these sections can run to hundreds of comments at a time.
     Subscription: blogs can be subscribed to, usually via RSS technology, making it easy to keep up with new content. Blogs are easy to set up using any of a number of services. One of the simplest is the free Blogger service from Google. Others such as Wordpress and TypePad offer more features, the latter for a fee.

     Source: What is Social Media? (Antony Mayfield, iCrossing) e-book