Read an internet search engine looks for a certain keyword for more information.
When an internet search engine looks for a certain keyword in a sequence of websites, the probability of the websites, containing that keyword, to show up on the search results page can be estimated to an extent. It is believed that around 20% of the websites contain that specific keyword.
How a Search Engine looks for a Keyword
A search engine is based on an algorithmic program that searches the web for websites containing a keyword that is being searched for. While performing the search, the search engine algorithm searches for a keyword in nine different databases in random order. As reported, only five out of the nine databases contain the given keyword. The frequency and location of the given keywords within the Web page determines its chances of getting ranked up in the search result.
Moreover, Google uses link popularity as one of the search ranking factors when the internet search engine looks for a certain keyword, therefore it is tougher to manipulate the Google ranking system.
Here are more details on how the internet looks for certain words