It is a glue-y, gummy thickener which adds fiber (body), smooth texture and helps "glue" ingredients together (eggs do these things, too).

I add 2 teaspoons to a chilled, watery Atkins shake (plus 1/2 teaspoon baking powder to "activate" it), plus 2 drops of stevia, and mix in a blender for a couple of minutes. It makes a very THICK, smooth, rich pudding.