Why Google Update its Algorithm ?

[egrovesystems]

i heard a info about Google about its algorithm updates.

By this updates some sites went to more down but some down site sites came to high page rank. i don know what are the calculation occurring in their algorithm.

And how do i know about this calculation in online. or i have to meet Larry Page to know about this.

[veikoh]

The original Page Rank algorithm is described here - The Anatomy of a Search Engine
Recent updates of Google's algorithm have well described here- How Google's Panda Update Changed SEO Best Practices Forever - Whiteboard Friday | SEOmoz

[treelifedesigns]

Google updated its algorithm because people learned how to abuse the system. To stay relevant in search industry that had to have quality search results so it was necessary.