What is SEO?
SEO refers to Search Engine Optimization, is used to optimize a website in order to make it find able via search engines like google, Bing etc. It is a practice of increasing the quality and quantity of traffic on a website.
How does a Search Engine works?
When you search for something on web, you are presented with a result of list from all over the web. How does a search engine find web pages with matching content and decide their ordering.
This happens in three steps:
Crawling and Indexing
Actually when you are searching the web, you are actually searching the index of web or the content which can be found on web. This is done using software programs called “spiders” or “crawlers”.
Spiders start by fetching a few web pages then they follow links on those web pages and fetch the pages they point to, and follow the links on those pages and fetch the pages they link to and so on until a big chunk of web is indexed across millions of machines. You can skip a page from crawling using robot.txt
Serving the answer
Now suppose you search how fast a bird can fly. You type in speed of a flying bird and hit enter.
The software searches index to find every page that includes those search terms. In this case there are hundreds of thousands of possible pages. How does a search engine decide which few documents i really want?
Simply by asking questions, too many of them. Like how many time does this page continue you keywords. Does the word appear in title, in the URL. Does the page contains synonyms for those words? Is it from a quality website? Whats the page’s page rank?.
A page rank is a formula that rates the importance of web page by looking at how many outside links point to it and how important are they.
Finally all these factors are combined the calculate page’s overall score and send back the search results.
Learn more about How does a search engine works and Google’s crawler Googleboot