The term search engine is used loosely in the Web community to include both search engines and information portals. However, the two are vastly dissimilar. A search engine, such as Alta Vista or Google, uses a robot or spider program to browse the Web following hyperlinks (web links) and indexing the content it finds. Therefore a search engine will eventually find your page, assuming that a link to your site exists somewhere on the web.
It is extremely difficult or almost impossible to find out how long it will take your site to be discovered. Therefore it is important to submit your site to the search engines especially the popular ones. Submitting your site speeds up the process exponentially and increases your chances for higher placement in search results, thus allowing you some control over placement.
On the other hand, an information portal differs from a search engine in that it will only find web sites based on manual submissions. Thus, if you do not manually submit your site to the information portal, it will never know about or index your site, and never list your site in search results. Some information portals visit your web site after you register it to determine the content and its relevance to the submitted topic. After the review, you may receive an e-mail message requesting additional information so a web site description can be created before the site is placed in the portal.
The advantage of information portals is that search results are most likely to contact high quality content matches to each query. However, increasing the chances for a higher placement in search results is usually not within the full control of the owner or manager of the web site.
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