surf:drawString

surf:drawString(str, x, y[, b, t])

• str (string)
  Drawing text
• x, y (int)
  Starting position
• b, t (background + text colour)
  Background and text colour

Not to be confused with surf:drawText.
Draws the text on the surface (character layer).
This is only supported on ComputerCraft outputs, since it's the only one with a character layer.