A TypeWriter-like script?

Do what dragonkeeper was doing except use my script since it will be shorter.

Inside the text label thing:

local text = "Watcha Doing"
for i = 1, text:len() do
    wait(.1) --You can change this to wait() if you want to make it type REALLY fast.
    script.Parent.Text = text:sub(0, i)
end

Determine the string length, then use a for loop to add each letter on and stagger it.

local string = "hello"
local stringlength = string.len(string)

for i = 1, #stringlength do
game.Players.LocalPlayer.PlayerGui.typewriter.Text = string.sub(string, (stringlength - i))
i = i + 1
wait(1) -- how long you wait for each letter to appear
end

I'm not allowed to give you the script but I can give you some hints

You will need functions http://wiki.roblox.com/index.php/Function

Remember to use PlayerGui to edit the text not StarterGui http://wiki.roblox.com/index.php?title=API:Class/PlayerGui

For having the text "TypeWrite" use wait() in the code

game.Players.LocalPlayer.PlayerGui.typewriter.Text = "t"
wait()
game.Players.LocalPlayer.PlayerGui.typewriter.Text = "ty"