Internet Basics: A Search Engine is Like a Librarian

Ever tell a librarian you want to find out about the Bermuda Triangle? Or maybe planting perennial bulbs? Or raising pit bulls? It probably didn’t matter what you were interested in, the librarian could point you in the right direction. Yet that’s all she did, point you in the right direction. She didn’t tell you the answer to your question. Why? Because she hasn’t memorized all the books in the library!

That’s what a search engine is like (kind of).

You ask it a question about anything, and it will spit back where you can go to look for it (or 100 000+ places you can go to look for it). The librarian told you to look in such and such a section of the library, while the search engine provides links you click on to go to specific websites.

The librarian knows where to point you because the library is organized into various areas of common interest, and the books are organized in a particular order. But the Internet is a little more willy nilly than that. And that makes the search engine’s job a lot more difficult than the librarian’s. Why?

Because that means the search engine has to read and memorize all the webpages first, so that it knows what’s in them. That way, when you ask about pit bulls, the search engine doesn’t just point you toward the “pets” area. Instead it says, “Ah, pit bulls. Of the 8 billion+ webpages I’ve read recently, here are the ones that talked about pit bulls.”

Obviously the search engine has to have a pretty good memory. Actually, it uses a database, which is just a way for computers to store information into specific slots for quick and easy retrieval later. When the search engine “reads” through all the webpages available out there, it makes note of what those webpages talk about. So when you ask about planting perennial bulbs, it’s no problem for the search engine to search through its own database of information and provide links for you to go to the very same pages it’s already skimmed that deal with tulips and the like.

And that’s why a search engine is like a librarian.