How do keyword searches work is a question asked by those of us that want a clearer vision inside the process of how search engines work.
The simple way of looking at this, is to first envision many pages of information on website pages stored on web servers all over the internet. The search engine has set up an indexing system, that is accessed by a software program nicknamed spiders.
How the keyword searches work is when you access a search engine and type in a word or phase in the search block, the search engine spider goes to work at locating something in the indexes that matches your search query. The spider looks at numerous pages and apply a system of algorithms to analyze the way these pages link to other web pages. By checking how pages are linked to another, the search engine can determine what a page is about, and determine whether the keywords of the linked pages are similar to the keywords in the original search query.
In the final analysis the spider decide on a group of relevant pages that appear to be the closest matches to your search query and displays those findings on the screen as search results.