Search Engine Optimization (SEO) is the process of getting your site to show up higher in Google (and others like Yahoo or Bing) for a specific search term or keyword. If you owned a site that was currently in the 5th position for “Video Game Reviews” and you wanted your site to rank 3rd or better, you would do something called Search Engine Optimization to help your site move up higher.
Why do SEO? Of course, we want to do this because the higher we show up for our search terms, the more people will click from Google to our site. The difference in traffic from the site that shows up #1 to the site at #2 can be dramatic. And needless to say, if you show up 11th or worse (which is off of the first page) you will get very, very little traffic. In general, you want to be AT LEAST #5 or better for your main terms.
The Two Factors of Ranking Highly
There are two things required to rank at the top of the search engines. With both of these elements in place, your site should see high placements. But if you are weak in either, ranking will be almost impossible. They are: relevant content and links...
It may seem obvious, but I will point it out anyways. If someone types video games into Google, your site on the topic of carpet cleaning will not show up. This is because Google will automatically know what your site is about. In a nutshell, it will check your site and say “okay, this site is about video games. When someone types video games into me, I will make sure that this site is somewhere in the mix.”
This is not to say that your site will automatically be at the top (remember, there are also millions of other sites about video games). This just means that Google knows which terms your site MIGHT rank for. To determine whether it is #1 or #1 million, we have to look at the second element...
After relevant content, there is another equally important factor: the number of links from other sites that are pointing to your site. This is an over simplification, but the site that has the most links pointing to it will rank higher than others. If your buddy links to your site from his, Google considers this to be a VOTE to push your site higher. If 5,000 people link to your site, you will be pushed much higher. Got that?
Repeat this until it makes sense: the more links a site has pointing to it, the higher it will rank.
That is rule #1 about linking, but there is also more too this linking stuff than just that. Let me illustrate by giving you a puzzle. Go to Google and type in “Click Here”. The first result should be either Adobe Reader or Apple Quicktime. Based on what we have learned, why would these sites possibly show up here? Neither of them say “click here” anywhere so the content is clearly not relevant...
The answer: there are so many other sites that point to Adobe Reader with a link that says Click Here (i.e. click here to download Adobe Reader). The point I am getting to is that what the link actually says matters immensely. If someone points to your site with a link that says: YourSite.com, that will help you rank for YourSite.com. If they point to you with a link that says Learn to Knit, that will help you rank for Learn to Knit.
Remember, it's all about relevant content and relevant links. That's the whole game of SEO in a nutshell. Virtually all SEO work will be some variation of getting more relevant links or adding more relevant content.