SEO step 1: Basic methods of SEO

What is SEO?
Search engine optimization (SEO) is a set of methods aimed at improving the ranking of a website in search engine listings, and could be considered a subset of search engine marketing.

What are Keywords?
A "keyword" is whatever you type in when you search on Google. Although you may type in more than one word when searching many people still call it a keyword as opposed to a "keyword phrase" or "several keywords" for simplicity's sake.
When considering a search engine optimization strategy choosing the right keyword or keywords to optimize for is critical. You might say it's similar to choosing the right category in the phone book. Choose wrong, and nobody will be able to find you when they need to.

What are Meta tags?
Meta tags are bits of HTML code that are generally placed near the beginning of webpages. In the early day of the Internet, one could simply put their keywords in their meta tags and shoot straight to top rankings. But that was long ago and search engines don't weight meta tags as much as they once did. In fact, there's some speculation amongst SEO experts that meta tags don't affect rankings at all anymore.
Even if meta tags don't affect rankings, there is still one type of meta tag that can be important, and that's the meta description tag. The reason this tag can be important is because the content of this tag shows up on the search results pages in search engines like Google and is therefore visible to human beings. If that content is well-crafted it may influence someone to click on your link and therefore increase the amount of traffic driven to your website.