How to use the for loop start and end nodes?

[No1Idle]

Hi,
can someone explain to me how to use the for loop nodes? I can't figure it out

[somenewaccountthen]

Me neither.
I just want to do the same stuff to images from a folder. 'Load images for loop' Seems applicable.
No clue how that should work, can't find any docs on it either.

An abstract workflow that uses it would be nice.