According to Wikipedia, a blog is:
“a website in which items are posted on a regular basis and displayed in reverse chronological order. Like other media, blogs often focus on a particular subject, such as food, politics, or local news. Some blogs function as online diaries. A typical blog combines text, images, and links to other blogs, web pages, and other media related to its topic. Since its appearance in 1995, blogging has emerged as a popular means of communication, affecting public opinion and mass media around the world“.
Examples of blogs include Scobleizer, Boing Boing and even this humble site. There are a number of advantages that blogs enjoy that static websites do not. For starters it is as easy to publish a post to your blog as it is to write an email in Hotmail, Yahoo! or Gmail (the basic interface is almost the same). Your content will be ordered automatically and you don’t need to worry too much about uniformity. It is also really easy to add links, banners and even monetise your site. A big advantage of a blog is that many of them use a feature called ‘trackback‘ which creates linkages between sites and works as a kind of cross-referral system which can boost traffic to your blog.
Of course one big feature found in almost alll blogs is a RSS or Atom feed. These feeds are basically a version of the blog people can subscribe to with feed readers or feed aggregators which enable them to receive updates to a large number of blogs in one place very easily and without having to navigate to a dozen blogs to catch up. There are feed readers online (for example, Bloglines and Newsgator) and available for download. Feed readers enable you to receive updates to blogs pretty much the same way you receive new email in your email program.
There are two ways you can set up a blog. You can either use a hosted service like TypePad, LiveJournal, WordPress or even Blogger (of these options, WordPress, LiveJournal and Blogger are free) or you can install a blog on your own server using MovableType and WordPress blogging engines, just to name two. There are dozens of content management systems which you can use to create more involved sites that go beyond a simple blog and if you are interested in these, take a look at software like Joomla and Drupal.
WordPress (the hosted solution) is a fairly new service and is probably one of the best hosted services for bloggers who don’t want to tinker with code and are happy to just climb on and start blogging in about 5 minutes.
Here are a couple more links which may be of interest: