Basically, it is to be distinguished between two different kinds: the mono-track and the multi-track curtain rod. Here, the mono-track rod is standard which is assembled in the form of a round pipe or inboard slot rod. The inboard variant offers the advantage that the curtain can be fixed on the curtain strip by means of pleat gliders and then be drawn through the complete width. Two- or multi-track rods offer the possibility to fix more than one curtain to the window.
A classic example is the hanging one curtain into the frontal and the net curtain into the rear track. This version is often used in museums and hotels where large window surfaces are to be covered.