Functions can have arbitrarily defined arguments defined in the opening line and subsequently used within the body of the function. Your parameters can be called any valid Lua name. Below is a simple function without arguments, followed by another function that calls on the first: function MyAddon_Mimic() DEFAULT_CHAT_FRAME:AddMessage("Hello World!") end function MyAddon_Call() MyAddon_Mimic() end Now the same function with arguments (you can define any number of arguments):