= Wave function
{title2=$\psi$}
{wiki}
Contains the full state of the quantum system.
This is in contrast to classical mechanics where e.g. the state of mechanical system is given by two real functions: position and speed.
The wave equation in <position representation> on the other hand encodes speed in "how fast does the complex phase spin around", and direction in "does it spin clockwise or counterclockwise", as described well at: <video Visualization of Quantum Physics (Quantum Mechanics) by udiprod (2017)>. Then once you understand that, it is more compact to just view those graphs with the phase color coded as in <video Simulation of the time-dependent Schrodinger equation (JavaScript Animation) by Coding Physics (2019)>.