Definition: We challenged ourselves to create a visual language for our users that synthesizes the classic principles of good design with the innovation and possibility of technology and science. This is material design. This spec is a living document that will be updated as we continue to develop the tenets and specifics of material design.
Goals: Create a visual language that synthesizes classic principles of good design with the innovation and possibility of technology and science. Develop a single underlying system that allows for a unified experience across platforms and device sizes. Mobile precepts are fundamental, but touch, voice, mouse, and keyboard are all ﬁrst-class input methods.
Source: Google Material Design
So Material Design is nothing more than a visual specification built by Google.
But you can use or implement it on every kind of visual applications such as…
… and with every kind of frontend technologies, frameworks or libs:
So I decided to create, update and maintain a list of Material Design Resource to help everyone to access easily and quickly to Material Design: