After you have built a website and optimized it by tuning its meta tags to the best, it is the time to get it submitted to major search engines and directories. So, that your site gets indexed by the search engines and the directories. There are lot of confusions in submission to search engines and web directories. Here, I would try to clear this confusion. A close study of search engines and web directory will sure help to solve this confusion.
search engines
When you submit your website to a search engine, it reads your site meta tags, looks their relationship with the contents, indexes you website and assigns a rank to your site according to the algorithm it follows. Here, you should understand that by submitting your site to a search engine does not mean that you will start getting high traffics just after its submission. This simply means that now the search engine knows about your site and its pages and would place you in its SERP (Search Engine Result Pages) according to your rank in its index.
You must have read very often about the offers for submitting your site to thousands of search engines for a fee, no matter small or big. No doubt that there are really thousand of search engines on the web but most searches are routed through a few major search engines like Google, Yahoo, MSN, AOL, alltheweb etc. If you submit to these search engines alone, it is really enough to get noticed in the search engine world. I am giving their site submission URLs and little info about their strategies.