People generally use this paper for walls as a thin sheet of paper to prepare a wall before decorating it.
It is suitable for use before paint or hanging wallpaper and can be used on both walls and ceilings.
Generally used to mask imperfections and create a smooth surfaces, if your wall has any hairline cracks in it, often a decorator will prepare the wall with a strip of lining paper before undertaking any decorating work.
It is a quicker and potentially cheaper way of creating a surface suitable for decorating rather filling the cracks, waiting for them to dry and then sanding.