OUseful.Info, the blog…

Th third episode of the OU/BBC co-produced Virtual Revolution (which may well be available on iPlayer from time to time) has just aired, and included a quick overview of how Google works – from finding relevant search results, to pricing the adverts that make Google its money.

So here’s a quick recap, and a little more detail…

Firstly, the famous PageRank mechanism that drives Google’s search results ranking. Here’s how Terry Winograd, one of the interviewees on the Virtual Revolution programme, describes it:

(Michael Nielsen has written an even more comprehensive tutorial on how this works at Lectures on the Google Technology Stack 1: Introduction to PageRank. If you want to read the original PageRank paper, you can find it here: The Anatomy of a Large-Scale Hypertextual Web Search Engine.)

Next up, Google’s chief economist, Hal Varian, explains how the advert auction that powers Google’s AdSense service works:

(If you buy Google AdSense adverts, you might also be interested in how to price your bids effectively…)

For a full length lecture by Hal Varian on “The Economics of Internet Search”, check out the following hour long video:

[To learn more about effective searching on the web, see the OU course Beyond Google: working with information online, or check out this free tutorial from the Open University Library: Safari: Skills in Accessing, Finding and Reviewing Information.]