A blog is when someone posts a comment or comments online to a public audience. This can be done in the form of text, audio or video. This can be done on social software such as Facebook or Myspace, or on dedicated blogging sites like this one. Blogs are extremely useful as means of communication and expression, and sites such as Facebook have gained huge popularity.I have been asked to start and keep an online blog to make me more aware of my online identity; it is very easy to forget that things published on the web can't be private, but can in fact be open to anybody; you are opening yourself to an unknown audience. Blogs, or in fact anything else that is put on the web, can be stay on the web for indefinite amounts of time, and can also be searched for, and so viewed by people you might not want to have your stuff viewed by.

The term "weblog", or "blog", was created by John Barger, and on December 17 1997, he started writing posts on his Robot Wisdom site. Blogs quickly gained huge popularity, and Facebook, for example, has over 100 million users.

When you write a blog on your profile, or write blogs on other profiles or anywhere on the web, you are creating an online identity for yourself. This identity's reputation must be maintained, and you should keep to the same degree of restraint as you would in the real world.