I am trying to make a kill function but it is not working can someone help me?

function die(hit)
	if hit.Parent:FindFirstChild("Huminoid") then
		hit.Parent.Head:Destroy()
	end
end
die()

I am trying to make a function that kills the player when they touch the parent of this script but it keeps on saying: Workspace.Part.Script:2: attempt to index local 'hit' (a nil value)

###Use http://wiki.roblox.com/index.php?title=API:Class/BasePart/Touched

So:

script.Parent.Touched:Connect(function(hit)
    if hit.Parent:FindFirstChild("Huminoid") then
        hit.Parent.Head:Destroy()
    end
end)

So the issue you were having is that you were calling the function not only once, but with no arguments, you need to call it when something touches a part.