If you are a computer user who access web for various needs, you SHOULD have used search engines for finding information you are looking for. Some of the search engines such as Google and Yahoo have almost become household names. If you use search engines for day-to-day work, isn’t it worth to see how they really work and deliver what you are looking for within seconds time?

Usually a search engine works in three steps. First two steps are not visible to the end user but they are vital for the accuracy and the efficiency of the search engine. An end user interacts only with the final steps of the process.

The first step is called “Web crawling”. There are several names for this step including web spider, web robot, bots etc. Most of websites especially search engines use web crawling for maintaining up-to-date data. Web crawlers are either software programs or automated scripts that browsers web in a methodical manner. Then they pass whatever the information they are supposed to pass to a central server or a database. These web crawler software or scripts can be configured to look for specific things such as web page titles, to where these web pages are linked and how many times they have been linked. This is vital information for techniques such as “Page Ranks” in Google.

The next step is called “Indexing”. Once web crawlers pass collected information to a central location, index mechanism collect, parse and store this data in an effective manner. This is done for making the web searches fast. That’s why your results are returned with a fraction of a second time. Otherwise, just imagine if these search engines search for your information through the web online (like “Windows Search” searches for a file taking minutes), how long will you have to wait in front of the computer for results? Search engines such as Google and Yahoo! do make online documents, media content and graphics searchable through the search engine in an instant by using indexes.

The final step is “Searching”. This is where you and I interact with the search Engine. Searching is entering queries in various forms which are entered by the end user to satisfy their needs. Then the search engine looks for the matching patterns in its index and displays the results in search engine’s results page. Now, this is how your favorite search engine works!