kubernetes quota vs limit. What are they? How are they different? When should I use one or the other?

I have been reading through the docs but it still is not clear as to why I should use one or the other. They have great examples of how to configure them but don't answer the why for quotes or limits very well.

I want to understand

kind: ResourceQuota

and

kind: LimitRange

I am not so interested in the yaml this is very clearly given in the examples.I want to understand the use-cases better.