can you call a function inside itself?

I know you can call functions inside other functions. But can you call a function inside itself?

I would test this but right now at work and decided to edit one of my codes. Here's a snipit of my code so you know what I'm trying to ask.

function check()
  if s == 16 and turtle.getItemCount(16) >= 1 then
    print("Turtle ran out of resources to build with")
    print("Please refill turtle with needed blocks and")
    print("press any key to continue building")
    os.pullEven("key")
    s = 1
  end
  if turtle.compareTo(16) == false then
    s = s + 1
    turtle.select(s)
    check()
  end
end

That's known as recursion. It's a useful tool for certain things, but if you just want code to keep looping, use an actual loop.