Direction and Change
Triangles are dynamic symbols used to indicate direction, change, or warning. Because they point so clearly, they are the standard for "Play" buttons and drop-down menus in user interfaces.
Mathematical Significance
- Delta (∆): The Greek capital letter Delta is used in science and math to represent "change" or "difference" (e.g., ∆ for change in velocity).
- Nabla (∇): An inverted triangle used in vector calculus to represent the gradient, divergence, or curl of a vector field.
The Warning Sign (⚠)
The universal symbol for caution is an exclamation mark inside a triangle. In Unicode, this character (⚠) is often rendered as a yellow emoji on mobile devices, but as a black-and-white text symbol on many desktop operating systems.