Among Find, Single, First, which one is the fastest?

Question

I want to minimize the time needed to retrieve a single unique element from a list. Which one is the fastest method among Find, Single and Fi

Answer 1

The fastest (for a large set) would be to have them keyed against a Dictionary and use that.

Single and First do different things; Single always iterates the entire set, even if it finds it at the start of the list, so First would usually be quicker than Single since it short-circuits.