Material Design is Google's signature style when it comes to designing their apps and websites.
A significant part of Material Design is the colors used and you've probably seen many material design examples with lots of vivid colors.
Choosing colors can be difficult when creating an app or website, you don't want them to clash or be harsh on the eyes. Material Design combats this by using a pallette of preset colors to help you get the right combo. This video is a brilliant example of that which every designer should watch.