You've seen it in the produce section, on the grocery shelf, even in food magazines. Maybe you've eaten it without realizing, in a Chinese or Japanese restaurant. Tofu is like fresh cheese.
Cheese is precipitated from milk, tofu from soybeans.
However tofu is used fresh, and cheeses are aged with salt. They are both good sources of protein, but cheese comes with a hefty dose of fat, much of it saturated, which is best consumed in limited amounts. The little or moderate amount of fat in tofu is not the artery clogging kind, and it's cholesterol-free, vegetarian for those that care, kosher and cheap. Soy products, especially the isoflavones, have been shown to offer a myriad of benefits, including possible prevention of many kinds of cancer, heart disease, diabetes, osteoporosis, for starters. In general, soy shows great promise for health promotion.