How search engine works: We all use a search engine every day,but do you know how it works? When you type into Google (or any other search engine), let’s say you want to know about making cakes and you entered “make cake” (without double quotes), you get some results.
If you look below into the organic results, your query is highlighted in the title and the text of the results to show you that those are the results that came. Now, there are other results you get when you do a search, these are advertising results. People have actually paid for these advertisements and they pay Google every time someone clicks on them.
How search engine works:
Googlebot, the google bot is also known as a crawler or spider. Web Pages are scanned by spiders/crawlers. These crawlers find your content by following links. To find your website, search engines are relying on other sites linking to it. Once they are on your site, they jump between pages using the same links that your visitors would. Links from external sites are like a vote for your content. Once a crawler hits your page, the page is analyzed and the content is evaluated.
Note: Crawlers cannot see content in the images or flash. In such cases, marketers should use alternative text for images which are important when it comes to search engine optimization.
A simple way to understand what crawlers do is to think of it as an explorer sent by the search engine.The search engine wants to discover new content on the web very much like an explorer out in the seas looking to discover new land. The reality is that the crawler is a computer program that travels from one page to another following link. A crawler then indexes the page so that it is available to use as a search result.