Live Load

If you wiggle about on a chair, sit down suddenly, jump up and down or walk along a plank you are applying a dynamic or [https://en.wikipedia.org/wiki/Structural_load#Imposed_loads Live Load to the structure.

Live Loads may be many times greater than the dead loads and often much more difficult to deal with because they can involve sudden changes in size and direction. Strong winds for example can often be the cause of a structural failure.