The two penalties are:

* Algorithmic Penalties – They include content spam, keyword stuffing, cloaking, sneaky Javascript redirects etc. If one of these or other related discoveries are made by Google on your website, your site will be penalized. To remove the penalty, you must fix the issues on your website, then Google will detect them and would return your website in its search results again.
* Manual Penalties – In case of a manual penalty, the length of the penalty depends on how severe the penalty is and how badly your site has violated Google’s webmaster guidelines.