More about Search Engines

Time for some more questions and answers.

Q. From the way Google handled our "questions"--not just the main one about the blue sky, but also the ones about the common words it wouldn't deal with--you'd think that a machine was behind it all, wouldn't you? 

A. Yes, which leads to principle No. 1 about search engines:

Principle No. 1: There's nobody out there.

Q. Meaning?

A. Meaning (you probably knew this) that Google runs on some very high-capacity computers using programs known as algorithms to process searches.

And to say that Google (or any search engine) "thinks," as we did on the previous page, is to be guilty of anthropomorphism.  Look it up in the Merriam-Webster Online Dictionary.

Q. Only a computer could search the web so fast, right?

A. Yes and no.  When you input a search to Google, you are not searching the web.  Which leads to...

Principle No. 2: You don't search the web; you search the databases of search engines which have already searched the web and saved the results.

The typical search engine has a program―sometimes called a "spider"―which "crawls" the web and gathers pages.  The pages are stored, or "cached" on the search engine's server.  When you do a search, you don't search the web; instead, you search the search engine's database of cached web pages.  Then when the search engine shows you the results of your search, it gives you links to the actual pages.

Q. Wait a minute!  "Spiders" that "crawl" the web?!  How does this really work?  How do these "spiders" decide which pages to include in the search engine's database?  How can a search engine possibly store the whole web?  Why does one page containing my search terms come to the top of the list and not another?

A.  More great questions!  We'll try to answer them next.