Social Voting

Internet search engines are those exceptional sites on the Web that are designed to help people find data and information stored on other sites. There is a difference in the way that how various search engines work,  a web search engine is designed to search for information on the World Wide Web and FTP servers. The search results are generally presented in a list of results and are often called hits. The information may consist of web pages, images, videos, news information and other types of files.

Search engines have become an integral part of our lives, good news about the Internet and its most visible component, the World Wide Web, is that there are hundreds of millions of pages available online, waiting to deliver information on an amazing variety of topics. Search engines use automated software programs known as bots or spiders to survey the Web and build their databases. Web documents are found by these programs and analyzed.  Data collected from each web page are then added to the search engine index.  When we enter a query at a search engine site, our input is checked against the search engine’s index of all the web pages it has analyzed. The best URLs are then returned to us as hits, ranked in order with the best results at the top.

Different search engine function differently but some basic task they need to perform such as:

•    They search the Internet or select pieces of the Internet based on

       important key words.
•    They keep an index of the key words they find, and where they find them.
•    They allow users to look for words found in that index.
•    Human-powered listings.

Here you will learn that how Internet search engines put the pieces together in order to let you find the information you need on the Web.

Web Crawling:

Before a search engine can tell you where a file or document is, it must be found. To find information on the hundreds of millions of Web pages that exist, a search engine employs special software robots, called spiders, to build lists of the words found on Web sites. When a spider is building its lists, the process is called Web crawling.

Crawler-based search engines, such as Google, create their listings automatically. They crawl or Spider the web, then people search through what they have found. If you change your web pages, crawler-based search engines finally find these changes, and that can affect how you are listed. Page titles, body copy and other elements, these all play a separate role.

Meta Tags:

Meta tags allow the owner of a page to specify key words and concepts under which the page will be indexed.  Some search engines are now indexing Web documents by the meta tags in the documents’ This is obviously very important if you are trying to draw people to your website based on how your site ranks in search engines hit lists.

What this means is that the Web page author can have some influence over which keywords are used to index the document, and even in the description of the document that appears when it comes up as a search engine hit.  This can be helpful, especially in cases in which the words on the page might have double or triple meanings the Meta tags can guide the search engine in choosing which of the several possible meanings for these words is correct.
Google, currently the most popular search engine, does not index the keyword meta tags.  Be aware of this is you are optimizing your webpages for the Google engine.

Building the Index:

Once the spiders have completed the task of finding information on Web pages (and we should note that this is a task that is actually not completed yet. The constantly changing nature of the Web means that the spiders are always crawling), the search engine must store the information in a way that makes it useful

In the easiest way, a search engine could just store the word and the URL where it was found. In reality, this would make for an engine of limited use, since there would be no way of telling whether the word was used in an important or a trivial way on the page, whether the word was used once or many times or whether the page contained links to other pages containing the word. In other words, there would be no way of building the ranking list that tries to present the most useful pages at the top of the list of search results.

Human-Powered Directories:

A human-powered directory, such as the Open Directory, depends on humans for its listings. You submit a short description to the directory for your entire site, or editors write one for sites they review. A search looks for matches only in the descriptions submitted.

Changing your web pages has no effect on your listing. Things that are useful for improving a listing with a search engine have nothing to do with improving a listing in a directory. The only exception is that a good site, with good content, might be more likely to get reviewed for free than a poor site.