Glad you asked. SEO is short for search engine optimisation. What follows is a brief introduction to SEO, especially as it relates to keywords and copywriting.
Search engine optimisation helps your website to rank highly in Google searches (and other search engines too, of course). In many ways, it’s a science and a black art rolled into one. Perfecting it is complex, but getting the basics right isn’t really all that difficult.
The situation is that the search engines are in a constant battle with people who create web sites – some of whom are spammers and others who simply want lots of traffic.
Search engines want to give people the right information, which means relevant information. Of course, if you’re creating a web site, the search engine doesn’t necessarily believe what you tell it. You may say (in your meta tags and site description) that your site is about such and such. But are you telling the truth? (Pornographers and spammers typically lie).
So Google takes a look at what your site is really all about, by reading the copy. Or rather, by getting its robots to read the copy.
This, of course, means that the copy on your website has to be carefully written. You need to think about the search terms people will use, and use these throughout your website. Ideally, you need to concentrate keywords together on certain pages. You need to aim for a density of keywords that will make that page rank highly for that search term.
So why not just make a long list of keywords and put them on every page? Because Google and other search engines aren’t so easily fooled. Google looks for relevant use of keywords in real sentences and tends to ignore lists.
You also need to get the “density” right. If you use a particular term too often, Google will think you’re spamming – and could blacklist you.
Google also spots tricks like invisible text (white on a white background). Trying to fool Google can be very counter-productive and it can get your site blacklisted.
The best way to convince Google that there is plenty of relevant content on your site is to have plenty of relevant content. Which means you either write some yourself, or get someone to write it for you.