Google is constantly updating their search engine algorithm, when they do a big update it’s generally given a creative name. The latest update is the Penguin update and many businesses have experienced decreased rankings after this update.
The Penguin update was marketed by Google as being aimed at fighting web spam by penalizing sites that were part of link schemes, cloaking, duplicate content or keyword stuffing.
Unfortunately some businesses who were not engaged in web spam got hit as well, if this is you, then you want to read this guide from Mashable: https://mashable.com/2012/08/15/guide-google-penguin-recovery/
