In brief
animation-timing-function determines progression through time. linear and ease can have identical durations but distribute change differently.
Useful to know
animation-timing-function determines progression through time. linear and ease can have identical durations but distribute change differently. [1]
When comparing effects, keep starting and ending values fixed too. Otherwise a difference in distance can be confused with acceleration. The function describes pacing rather than creating new endpoints.
Sources
For further detail and to check the information: