What happens to the food that is not digested?

I know that almost all food is digested- even the large insoluble food of protein, starch and fat. But what actually happens to the food that is not digested?|||Any food that your body cannot process or extract nutrients (e.g. cellulose from the cell walls of plant cells) is excreted from your body as feces|||it gets excreted as faeces|||it just gets pooped out as "roughage". just moves out undigested.