What is a Blog?

A blog (from weblog) is a website, usually maintained by an individual (sometimes more than one individual), with regular entries of commentary, descriptions of events, or other material such as graphics or video. Entries are commonly displayed in reverse chronological order (in simpler words "most recent one on top" . "Blog" can also be used as a verb, meaning to maintain or add content to a blog.
Many blogs provide commentary or news on a particular subject; others function as more personal online diaries. A typical blog combines text, images, and links to other blogs, web pages, and other media related to its topic. The ability for readers to leave comments in an interactive format is an important part of many blogs. Most blogs are primarily textual, although some focus on art (artlog), photographs (photoblog), sketchblog, videos (vlog), music (MP3 blog), audio (podcasting) are part of a wider network of social media. Micro-blogging is another type of blogging which consists of blogs with very short posts. As of December 2007, blog search engine Technorati was tracking more than 112 million blogs. With the advent of video blogging, the word blog has taken on an even looser meaning of any bit of media wherein the subject expresses his opinion or simply talks about something.

Ok.... so what are the various things people should be aware of that is directly or indirectly related to blogging?
The answer is as below

The Blogosphere
The collective community of all blogs is known as the blogosphere. Since all blogs are on the internet by definition, they may be seen as interconnected and socially networked. Discussions "in the blogosphere" have been used by the media as a gauge of public opinion on various issues. A collection of local blogs is sometimes referred to as a bloghood.

Blog search engines
Several blog search engines are used to search blog contents, such as Bloglines, BlogScope, and Technorati. Technorati, which is among the most popular blog search engines, provides current information on both popular searches and tags used to categorize blog postings. Research community is working on going beyond simple keyword search, by inventing new ways to navigate through huge amounts of information present in the blogosphere, as demonstrated by projects like BlogScope. Also there is google's very own blogsearch.google.com

Blogging Communities and Directories
Several online communities exist that connect people to blogs and bloggers to other bloggers, including BlogCatalog and MyBlogLog.

Blogging and Advertising (Interrelated)
It is common for blogs to feature advertisements either for the financial benefit of the blogger(earn money actually), or to promote the blogger's favorite causes. The popularity of blogs has also given rise to "fake blogs" in which a company will create a fictional blog as a marketing tool to promote a product.
These although are blogs, feature products for sale.

There are a lot of terms that you find here which might be greek and latin to most of you, I will break these down into decipherable information for the benefit of future bloggers.