Material Icons is Google's official icon language for Material Design; the material.io URL now redirects permanently to m3.material.io, the current Material Design 3 site, which documents icon guidance and points to the Material Symbols font as the actual delivery format.
Following Google's own icon guidance keeps an Android or Material-styled web app visually aligned with the design system it's built on, instead of drifting from a third-party reimagining.
Fits any product adopting Material Design that wants the authoritative icon guidance straight from Google rather than a community recreation.
As of this check, material.io 301-redirects to m3.material.io/styles/icons/overview: the destination is real and current, just no longer at the original material.io domain; actual icons ship via Material Symbols (fonts.google.com/icons) under Apache 2.0.
Beautifully crafted symbols for common actions and items, from Google's Material Design system.
