wiki.roblox.com/index.php?title=Loops#For
Basically, a for loop is where a code will execute the code inside of the statement a set number of times.
It would go:
for [Variable] = [Starting Value], [Ending Value], [Increment] do
--Code
end
The increment by default is 1.
The code will begin at the starting value and go to the ending value for each increment.
As said above, that for loop will execute the code 10 times.