The outer shape is a circle. Inside the circle is the outline of a square with the four corners folded inward. The shape inside the circle resembles a hollow plus sign.
This Positive icon is made in Material Design style
developed by Google. This style is based on extremely simplified shapes, thin two-pixel lines, and is optimized for 24x24 px. Unlike other vector icon packs that have merely hundreds of icons, this icon pack contains 6,000 icons, all in the same style and quality.