About felt....

Long considered the oldest form of man-made fiber, wool felt is created through the process of combining natural fibers to create a solid fabric.  Fibers can be combined by various methods: wet felting, needle felting, and good old shrinking-that-favourite-wool-sweater-in-the-washing-machine.

Wet felting requires the laying out of layers of wool roving (wool before it has been spun into yarn), adding hot water and soap and agitating the fibers until they weave themselves together.  The fiber mat is then agitated, rubbed, warmed and shocked until the mat becomes smaller and stronger.  Other fibers, both natural and synthetic, can be added in the layout process to create an endless number of textures and colours.

Needle felting requires a special barbed needle to push the wool roving (or yarn, or fur) into another fabric thus combining into one overall fabric.