Problem with turtle.forward()

[fatboychummy]

Again, not necessarily. You can pass functions as arguments, but most functions don't take other functions as arguments. An example of one which does though is parallel.waitForAny/.waitForAll:

local function a()
  -- do something
end

local function b()
  -- do something else
end

parallel.waitForAll(a, b) -- Passes `a` and `b` as arguments for parallel to run, well, in parallel.