Julian Bucknall discusses word indexing and document searches: if you want to know how Google works its magic this is the page to turn to.
How does Google do it?
Well. There are times when you can argue about something and there are times when you just have to accept the job you’re given. I stared at the screen at the email from Our Esteemed Editor. It started off with ‘Can’t remember if I’ve ever suggested this before...’ and went on to ask about a particular algorithm.
Ha! A ‘suggestion’, no less! Right! I can read between the lines as well as anyone, I didn’t get where I am today, etc. I dashed off a quick reply to the effect that my grandmother learned that algorithm whilst a teacher at Malory Towers (or was it The Chalet School?) and then secretly perused some algorithm books, sweat beading on the old brow. I brought up Google, which only made matters worse. How did they do it?