Is the value of parametes the value of the parameters when the function is called?

If I was to create this script

Button = script.Parent

function Add(One, Two)
	print(One + Two)
end

Button.MouseButton1Click:connect(function(Add)
end)

-- So, in parameters, I am assuming the value of the parameters, in functions, is the value of the --function of the parameter called correct?
--Example
--I call the function Add
--Add(1, 2)
--So the value of strings "One" and "Two" are the value of the parameter when the function is --called which is 1 and 2 right?
-- So it prints 3



-- Is this true?

Not exactly sure what you're asking, but I'll try my best to give some information on parameters.

So, let's say that we have a function that will create a part, and it takes in a few parameters: Size, Position, Color, and finally PartType. Let's go ahead and setup such a function.

local createPart = function(s, p, c, pT) -- You could also just do local function createPart(s, p, c, pT), same thing.
 if pT:lower() == "part" then
  local i = Instance.new("Part", workspace)
  i.Size = s
  i.Position = p
  i.BrickColor = c
  return i
 elseif pT:lower() == "wedge" then
  local i = Instance.new("WedgePart", workspace)
  i.Size = s
  i.Position = p
  i.BrickColor = c
  return i
 end
end

local myPart = createPart(Vector3.new(4, 4, 4), Vector3.new(0, 50, 0), BrickColor.palette(math.random(0,127)), "Part")

So, the above function sets up a function that, again, takes in some parameters for making a part. We can call this function and supply it the parameters that we want, and voila.

There's a lot you can do with parameters, so with the information you've been given, experiment around and you'll get the hang of it in no time.

Hope this helps, MINEBLOX106.