Meta Tags
Meta tags are placed in the <head> part of your web page. The two main ones for seo purposes are the Keywords and Description meta tags. These alone won't give you a good position in a search result (as they did in the early days of the Web) as very few search engines rely solely on these and some do not use them at all. However, don't ignore them.
Description: use this to provide a description of the web page. It is not used by many of the larger search engines, but it is used by smaller ones and inktomi. Again do not make it too long and don't pack it with too many keywords - definately do not repeat the same one over and over - as it could end up being ignored by some engines. Your description should also include your keywords and phrases.
Keywords: this is a list of words and phrases that you want associated with your site. This tag is not used by many serach engines anymore, but it is used by some (Yahoo?) so it is worth while spending a little time on this. Don't have too many keywords as some search engines will ignore them all if this is the case; and don't repeat keywords for the sake of it. Also, be careful about breaching copyright - using a competitor's name in your keywords might well fall foul of this. At the least make sure your selected keywords and phrases are in the list. Keep the list short - RankQuest suggest a 10 - 15 words at the most.
Have a look at Rank Quest for more information on making the most of your meta tags.