Summary: Rosin Paper is for floor covering. Masking Paper is for masking off small areas.
A light-duty floor covering (as opposed to a more costly and durable ram board type product).
The rosin paper in your link is a 3-foot x 167-foot roll; this would fit nicely in a typical hallway or stairway.
This product is used to cover large areas quickly but would not typically be used on walls.
Used to mask off horizontal or vertical surfaces to protect from overspray.
The masking paper comes in a 180-foot roll with options for different widths of 0.5, 0.75, 1, and 1.5 feet. It can be applied using a tape and masking film dispenser or by rolling it out and tapping separately.
Think of this product as a way of widening your masking tape. It is usually used as a precision covering and can often be combined with other products, such as used around the perimeter of a room on the floor up against the wall and then simply using drop cloths to protect the rest of the floor.
Plastic sheeting is what tends to be used to cover walls. It is much more manageable to install, especially if you have it folded up so that you simply tape it at the top of the wall and unfold the plastic sheet, which is long enough to reach the floor.