Search engine indexing is how information is collected, parsed, and stored in search engine databases to facilitate fast and accurate information retrieval. The search engine index design uses interdisciplinary theories from linguistics, cognitive psychology, mathematics, informatics, physics and computer science.

Search engine optimization is about creating a site that meets search engine criteria.

Automatic vs. Manual Submission
Search engines don't like automatic submissions. They get millions of attempted automatic submissions each day, and, as a result, go to great lengths to try to stop them, such as requiring passwords and/or fill-in details before the submission is accepted.

Automatic submission software is banned by many search engines and directories because it can't always place links in relevant categories. Whether you hire a directory submitter or use submission software yourself, you are setting your site up for failure. Getting too many incoming links too quickly or submitting the same site to the major engines repeatedly can be seen by search engines as spamming and get your site banned. There are few benefits to using a paid submission service, although the promotions tout that these services know of places to submit that you are unaware of. The best submission services take the time to educate their clients on submission with the expectation that they'll be able to do the job themselves next time.

Submitting your site manually gives you control over where you'll be listed. Automatic submitters may list your site with an engine you've never heard of outside the United States. Or, worse, they could be associating your site with sites that you find objectionable, such as pornographic sites. When you submit your own site, you decide what category to list in. You don't want your site to end up in the general directory or the miscellaneous category where it may never be seen.

Every site should be marketed differently, and submitted to different engines and directories depending on its intended audience. Automatic submission doesn't do this. Manual submission is the only way to choose the descriptions and keywords that you think will be most effective in promoting your site, as most engines and directories allow you to choose your own.

Common Myths of Search Engine Submission
Here are some common myths about submitting your site manually:

1. Search engine submission requires enormous research.
2. Almost every search engine and directory has a link labeled "Add a site" or "Submit URL," which takes you directly to their submission form. All you have to do is follow their rules and enter your information carefully.
3. Websites should be listed in all search engines.
4. If you list your website with the top-tier search engines, it will find its own way into the second tier and beyond. In fact, you don't even have to submit your site at all for it to be listed--search engine spiders are constantly combing the web and will eventually find your site on their own if your site contains links to other sites.
5. Websites should be listed on a weekly or monthly basis. Continually submitting your site can be classified as spamming and result in your site's banishment from a search engine's database. As a general rule, don't resubmit a new version of a page unless you have an unfavorable ranking.
6. Good submission is costly. The truth is you don't have to pay a submission service to submit your site to the search engines. Submission to most major search engines is free.

Search engines and directories you should submit your website to include:

* http://dmoz.org
* http://dir.yahoo.com
* http://www.joeant.com
* http://www.skaffe.com
* http://www.bluefind.com
* http://www.zeal.com
* http://www.goguides.org
* http://www.gimpsy.com
* http://www.wowdirectory.com
* http://www.sevenseek.com
* http://www.thisisouryear.com
* http://search.looksmart.com/Submission Service Claims