I’m sure if you are new to SEO, there are a number of terms you don’t quite understand, the most common term people have issues understanding, is a backlink, it’s a very common term in SEO-talk, the main reason being, SEO is more or less dependant on backlinks. The easiest way to think of a backlink, it’s a link from 1 website, to another website, so a link back to another website, very simple stuff, now they are so important, because without backlinks, your website would probably never be indexed, nor ranked for any keywords. Now when people talk about backlinks, keywords are usually next on the discussion list, now the way most people see it, the more backlinks you have, with the same keyword, the better your ranking will be in that keyword, it’s very true, you can read some more about the term ‘google bomb’, where you create mass amounts of backlinks containing the same keyword to a website, to push it to the top of Google. Obviously a load of people have taken advantage of this, it’s become harder to build backlinks, but you can read about these ‘google bombs’ which have been sent to quite a few people, including George Bush, here Source: http://www.alex-brooks.com/2010/01/29/what-is-a-backlink
I think most of us take for granted the things we know, all the while not knowing a lot of people do not know the things we know. LOL So we must share, good for you.
Another way to put it is that a backlink is a vote from another site towards your site-telling the search engines-this site must be valuable.