Tomorrow on 4/21/15 Google is releasing an update to it's mobile search algorithm which could hurt the rankings of many non-mobile friendly websites. Google sent out the warning back in February you can find it Here. Let me make this east for any website owner, a lot more people today are using their mobile devices to do searches, more than people who are using computers. Google knows this so they're making results more mobile friendly, but if your website isn't mobile friendly you will drop down in the search results that come up, potentially hurting your business and incoming website traffic which makes this update very important.
You can test your website Here using Google's Mobile Friendly Test.