Timestep (Delta Time)
In real-time applications, an important aspect is the ongoing loop in which systems like the renderer or physics are updated. In game development, this loop is called the game loop1.
The time that elapsed from the last iteration of the loop to the current iteration is often called Delta time and describes the time step. Timesteps in game loops can be fixed-time or variable-time.
Footnotes
1
A game loop can also refer to a loop that only updates the game world while something like rendering happens in a seperate rendering loop