Rail stands for:

• Response (to user's action)

• Animation

• Idle

• Load (page load)

• 0..10 ms - for all the computations during animation frame (6 ms retains for browser's work)

• 10..100 ms - the limit for the response to the user action:

  • 50 ms keep for the idle to be responsive (able to queue user actions)
  • 50 ms to all the calculations

• 100..1000 ms - the time users can keep a focus on tasks

• 1000..10000 ms (1..10 s) - users lose focus on tasks

• > 10 s - users may abandon the resource