Nowadays everybody talks about blogs. Everybody wants to have a blog. But what is it? 'Blog' is the short form of weblog. A blog is an online journal or diary, where everybody makes public their thoughts, comments, and philosophies, updated frequently and normally reflecting the views of the blog's creator. On Wikipedia, the blogs are sorted according to different criteria, which establish the way content is showed:

- by genre: political, sports, travel, fashion, xxx etc.
- by media type: vlog(blog for videos), linklog (blog for links), photoblog (blog for photos) and more.
- search engines for blogs: several search engines are used to search blog contents (also known as the blogosphere). Some blogs search engines provide current information on both popular searches and tags used to categorize blog postings.
- by legal status: for private use (most of existing blogs) or business blogs (blogs used for internal use in corporations and these are also known as corporate blogs)
- by device: there are also blogs written on a mobile device (PDA, mobile phone) and these are known as moblog

Although there are so many types of blogs, there are certain common characteristics. The main common feature is that a blog has a main area where the articles are posted. The articles are listed chronologically and are organized into categories. Also, the newest articles are posted on top and the oldest articles, on archives.

Another characteristic is that the users can post comments on the articles. The next feature is the blogroll. A blogroll is a list of sites considered by the blog author to be really interesting. If you want your users to keep up with the newest information posted on your blog, you can use feeds. A Feed is a function that allows "Feedreaders" to access a site automatically looking for new content and then post updates about that new content to another site.