Loops-when-to-use-which.md

Method	Runs through each item	Executes Given Function	Returns the result	Number of elements in result (compared to original array)
.map	✔	✔	in array	=
.filter	✔	✔	if true, in array	=<
.forEach	✔	✔	no, return is undefined	none
.reduce	✔	✔	in array or anything else	one, (a single number or string) Reduce transforms array into something else
for loop	✔	until condition is false, you know the number of iteration beforehand	They run code blocks, They aren't functions so don't need to return	>, = or <
while loop	✔	while condition is true, you don't know the number of iteration beforehand	They run code blocks, They aren't functions so don't need to return	>, = or <