Tick and Frame

Tick is the smallest unit of time recognised by the game model. Every tick the game model advances the current model state to create the next step in the simulation, by applying the rules of the game.

Frame is a graphical representation of the game state created by the renderer. Subframe rendering allows the renderer to interpolate between model states to create even smoother experience.

In discussions the term "frame" is usually used in place of "tick". This is a historic leftover from older games that painted only one frame per tick, making the terms virtually equal gameplay-wise.