In lua your frame would be
Code:
local frame = CreateFrame("Frame", "MyAddon_Frame")
frame:SetSize(100, 100)
frame:ClearAllPoints()
frame:SetPoint("TOPLEFT")
If you want to see it (all "Frames" are transparent by default) add:
Code:
frame.texture = CreateTexture("$parent_Texture")
frame.texture:SetAllPoints(frame)
frame.texture:SetTexture(" ")
Will create a green square which is the default when the texture file can't be found.
If you go
here you can find a list of all the widget type (start with "Frame" from the list on the right hand side) and their associated methods.