Amy N. Langville, Carl D. Meyer —Google’s PageRank and Beyond: The Science of Search Engine Rankings— Princeton University Press, 2006, 224 pp. ISBN 0-691-12202-4.
Langville and Meyer presents us the mathematics behind Page Rank, Google’s method of rank prioritization as well as other similar methods. If the first few chapters are concerned with the history of search engines and search methods, the remainder of the text is clearly mathematical in nature.
The theories presented in the book make extensive use of matrix/vector maths and the reader that is not very familiar with the topic may find it hard to follow, even though proofs are given with great details and the book contains an appendix on the mathematics needed to understand the main subject. This is not really an introductory level book, but rather a graduate-student level one; however, for the reader interested in search engines and in particular smart ranking, this is a must-read.
You should probably read it after reading Albert László Barabási’s book, Linked: How Everything is Connected to Everything Else and What it Means for Business, Science, and Everyday Life (at Amazon.com).