Link building has been the number one target for web designers and SEO professionals in recent years and even marketers spend loads of time trying to generate and find external links that will direct traffic back to their sites. The greater the number of external links, the more credibility given to a specific site, at least in the eyes of search engine crawlers.
What happens if you are just starting out though? and don’t have many links, how will you be ranked? This is what Matt Cutts says about it
“You’re pretty much judging based on the text on the page at that point. So, Google has a lot of stuff to sort of say the first time we see the word on the page count a little more, the next time a little more, but not a ton more, and then after awhile we say ‘we’ve seen this word, maybe this page is about this topic.”
Keywords then are the answer, but they absolutely must be included within the text as naturally as possible, and as frequently as would be normal when discussing a subject. Keywords stuffing strands out when you read content with it, and Google is of course smart enough to spot it.
To find out more about it from the man himself, here is the original video