Panda and Penguin: Google ranking algorithm updates

You may have heard chat about recent changes to Google’s search ranking algorithms, named Panda and Penguin.

Over a three week period in April 2012 these major iteration updates or ‘filters’ to the algorithm have affected how certain links and sites are perceived, and has caused some sites to slip or even completely lose their positions in Google search engine results pages (SERPs). So what are they in simple terms?

Google Panda
For on-page factors and usability.

Google Penguin
Equivalent filter targeting offsite factors and links.