Search engine optimisation can be done two ways. Firstly by making your content good, relevant, well structured and searchable. Or secondly by doing dodgy magic that tries to game the algorithms that search engines use. If you do it the first way by making your content good quality, you have a good chance of getting a high rank for a long time. If you do it the second way, you may gain in the short term, but long term, you are likely to be dumped down out of the search engine index when they spot your trickery. So if you want to learn about SEO, then you need to work out if whoever is teaching you is trying to teach magic to game search engine rankings, or how to actually do your site properly.
Personally I wouldn’t bother though, it isn’t exactly black magic – this document from google gives you the information you need, from the horse’s mouth:
http://static.googleusercontent.com/external_content/untrusted_dlcp/www.google.com/en//webmasters/docs/search-engine-optimization-starter-guide.pdf
Joe