To begin, it’s necessary to understand how Google penalties work. Google, of course, doesn’t just - poof! - make websites disappear. It makes websites disappear from Google rankings. However, since Google is the most used search engine, disappearing from Google makes your business the equivalent of invisible. You’re still there, but no one searching for what you do or sell will be able to find you on Google unless they type your address into the address bar.
Google has two types of penalties - manual and algorithmic. If you get a manual penalty it means that someone at Google deliberately targeted your website for Google punishment. The good thing about a manual penalty is that you’ll get a notification in your Google Webmaster Tools and you’ll have an idea of what you must do to have the penalty lifted.