A weblog, more commonly abbreviated to being called a blog, is a series of regular entries on a website or a part of a website, normally displayed in reverse chronological order, with the most recent at the top of the browser page. The entries are usually devoted to a certain topic and are often quite personal, written by the blog owner or other regular contibutors. Visitors to the blog are normally allowed to post comments to each article. If this is the case, the blog is called interactive.
The entries may be news reports, be in the form a discussion or a diary. Typically, a blog main contain text, images, audio and video files, and links to other blogs or websites with similar content or otherwise related content. The authors of blogs are called bloggers.
In the early part of the 21st century, blogging became one of the most popular forms of communication. A blog can unite a large group of users with common interests or background. Such blogs are devoted to discussions and informing users on events which may be of their interest. While personal blogs rarely reach outside the blogger's own family and friends, some can attract worldwide interest. For little or no financial outlay, bloggers can now publish their news or comments to the whole of the world wide web - a publishing reach that up to the late 1990s was only ever the preserve of multi-billion dollar multi-national publishing and broadcast companies.
Another type of blog is the corporate or organizational blog. It is often used for business purposes and may even be a part of the company or organization marketing policy. These blogs tend to be more popular, mainly due to the bigger number of people who are aware of their existence and read them.
A blog which contains predominantly videos is called vlog. One that features photographs is called a photoblog. There can also be microblogs (blogs which consist of series of very short entries), podcasts (consisting of audio files), or tumblelogs (comprising various media and short entries). All blogs are said to exist in a virtual "blogosphere," the word becoming commonly used as a collective for blogs and bloggers. Since all blogs are located in the Internet, they can be considered as interconnected. To help bloggers find their way through the millions of blogs, there are various blog search engines, such as BlogScope, Bloglines and Technocrati.
Blogs emerged as a form of online diaries in the 1990s. Justin Hall is regarded as the father of blogging, becoming famous in 1994 for his online diary Justin's Links From the Underground, which he started while studying at Swarthmore College. The term "weblog," a conjunction of the words "web" and "log", was coined in 1997 by Jorn Barger. By 1999, "blog," was being used, as both a noun and as a verb, with those blogging being termed bloggers. By 2002 there were more than 133 million individual blogs on the Internet; in 2008 there were 346 million people worldwide who read blogs. According to Technocrati, the majority of the bloggers are well-educated and well-off. Data for 2010 shows that two out of three bloggers are male and are aged from 18 to 44. In the United States, 74 percent of bloggers are college graduates. Yet for all this, only 10 percent of bloggers claim blogging as their main source of income.
By the middle of the first decade of the 21st century, many professional journalists from television and radio stations and newspapers were being encouraged by their employers and editors to adopt blogging as a means of creating some interaction with their viewers, listeners or readership, discussing their latest program or article, and providing a more immediate commentary on events than traditional media is usually capable of doing. Various political personalities and organizations have also recognized the power of blogging and joined the blogosphere.
Blogs and other news content available on the Internet have created problems for conventional media, particuarly newspapers, which suffered steeply declining circulations and advertising revenues. And while TV, radio and newspapers in most countries are subject to some form or regulation and bound by the laws of libel, blogs have tended to be unrestricted, and more difficult to censor. As a result several banned movements and organizations have found it easier to spread their ideas and promote radical beliefs. Bloggers in China, Egypt, Burma and Sudan have been sent to prison for posting their views online.