Geometric Shapes is a Unicode block that consists of 96 symbols referring to geometry at codepoint range U+25A0-25FF. Squares, triangles, rectangles, pointing left, right, up, down; transparent or painted shapes, striped or chequered ▦. It's absolutely up to you in what contexts to apply them.
For example, some look like buttons on a keyboard
or road signs showing direction
▻
. My favourite is this square
▮
, because it looks smooth and serene. Perfect for copying and pasting on social media!
Seriously speaking, geometric shapes come in handy if you specialise in art, design, or engineering. They are basically figures which represent the forms of different life objects. Some figures are two-dimensional, whereas some are three-dimensional shapes. In our case, we're talking about two-dimensional, of course. Although, this quarter-eaten pie on a plate
◴
seems pretty three-dimensional to me.