In Unity, what is the difference between Awake, Start, Update, FixedUpdate and LateUpdate?

What the interviewer wants to hear

• Awake runs when the object is loaded, before Start
• Start runs before the first Update if the component is enabled
• Update runs once per frame for game logic and input
• FixedUpdate runs at the fixed physics step
• LateUpdate runs after all Updates, good for cameras

Model answer

Awake is called when the object is created or the scene loads, even if the component is disabled, so I use it to set up references to its own components. Start is called once before the first frame Update, only if the component is enabled, so it is a good place for setup that depends on other objects already being awake. Update runs once per frame and is where I read input and run most game logic, using Time.deltaTime. FixedUpdate runs at the fixed physics rate, which may be zero, one or several times per frame, so I apply Rigidbody forces there. LateUpdate runs after all Update calls in the frame, which makes it ideal for a follow camera, so it moves after the player has moved.

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