How does a Search Engine work?
Each time you enter a word or phrase (say,”the five best desserts”) into a search engine, the following things happen behind the scenes in about one_ eighth of a second.
Most search engines build an index based on crawling, which is the process through which engines like Google, Yahoo and others find new pages to index. Mechanisms known as bots or spiders crawl the Web looking for new pages Then, the engine will return a list of Web results ranked using its specific algorithm.
It is useful to think about the words that you use in your search. Too few and you will get too many results, too many and you may get no results at all.
When you want to find the answer to a question, such as, What countries did the Vikings raid? You need to think about the important keywords.
You could just type the whole sentence into the search engine but it will probably ignore some words, like joining words and punctuation. Instead it might save time to search for keywords like ‘countries’, ‘Vikings’ and ‘raid’.
Search engine works following step:
Step 1: Search
The search engine uses algorithms (mathematical formulas) to determine exactly what you’re hunting for, adding in synonyms (“tastiest treats”), anticipating your terms before you’ve even finished typing, and offering corrections in case you’ve made a mistake (did you mean best deserts instead of best desser?
Step 2: Sort
Your request is sent to the search engine’s servers. Here, the company that owns the search engine maintains a massive index of all the words, photos, videos, songs, and other data strewn across the World Wide Web. This information-enough to fill hundreds of millions 0f gigabytes is continuously collected and updated by programs called Spiders that crawl across the Web and sift through its information.
Step 3: Collect
From its index, the search engine gathers every Web page with content that matches your search term. Results are filtered based on hundreds of factors, including the pages’ age ,the number of people who’ve visited the pages, their estimated reliability, and more .
Step 4: Result
The results are ranked as links in your Web browser. with the most relevant Web pages at the top of the list.