Why is Google Search so fast?
Google is undoubtedly the best search engine out there. For any query you make, you are always certain to find very useful resources on the first page. It can do this because it searches the whole web and ranks them in some order. The whole web? Really? The last time I searched something on google, it took only 0.36 seconds? Isn’t it crazy if it actually in that short time, goes through the whole web? Well, let me take you on a journey about how this is done.
What if I told you that google actually does not search the whole web whenever you make a search? I mean, if they did, that wouldn’t make sense right? They figured that, there has to be a way of doing this once and for all. So they basically indexed the whole world wide web? Whoa? What does this mean?
Basically, Google crawls through every webpage that exists and organizes the information in a very specialized graph that makes makes search very easy. This process is called indexing. Let me explain how this is done.
First they start from a webpage and take all the words on that page and store it in a giant database with a pointer to a list containing the url of webpage it was just found on. Now, they go to other webpages and do the same thing only that this time, when you find words that are already in the database, they just add the url to the list that the word points to. Let me give an example here.
Assuming we go to webpage 1 and we find the words – he, she, it; we will record it in our database as,
he –> [webpage1]
she –>[webpage1]
it –> [webpage1]
Now, if we go to webpage 2 and find words– me, they, he, it
Our database now becomes something like
he –> [webpage1, webpage2]
she –> [webpage1]
it –> [webpage1, webpage2]
me –> [webpage1]
they –> [webpage1]
What is the advantage of organizing all the information on the web in this format? Well, in case a user searches for the word “it”, all that has to be done is to go into our database and find the word “it” and get the list of webpages that are being pointed to by this word. In the case of google, they have an algorithm that also determines which page is ranked before the other. It is very evident that indexing once reduces the amount of time search engines have to take to get results for any queries made.
We see how by organizing the world’s information in a more specialized graph where each word that exists on the web is mapped to a list of all the pages that the word can be found on, helps us to find information very fast and without doing much work.