If tofu is anything, it’s unassuming. Naysayers pooh-pooh its jiggly texture and boring white hue, and even fans admit to its somewhat unappealing appearance. But those who get past its exterior learn that tofu is versatile and actually rather fetching when dressed up in marinade and seared on the skillet.

Taste isn’t the only reason both vegetarians and omnivores stock up on tofu. The soy foods industry rakes in $4 billion a year, thanks in part to reports on soy’s health benefits. Because it’s a complete protein, soy makes an excellent substitute for meat and fish. Not only that, but compared with animal sources of protein, soy is lower in saturated fat and is cholesterol free. About 3 ounces of firm tofu has 70 calories, 3 grams of fat, 2 grams of carbohydrate, and 7 grams of protein. (There is also light tofu, which has less fat and fewer calories.) Varieties that are processed with calcium sulfate are a good source of calcium. Soy also contains B vitamins and isoflavones, plant-derived compounds with properties that can lower cholesterol and may help relieve symptoms of menopause.

There remains a great divide among those who say soy promotes health and others who point to its side effects. Some research has linked soy isoflavones to a greater risk of breast cancer in women and lower testosterone levels in men. But the research—much of it done in rats—hasn’t amounted to much, says Andrea N. Giancoli, MPH, RD, a Los Angeles dietitian. “Whole soy foods can actually reduce breast cancer occurrence,” she says. But you’d be well advised to stick to soybeans and tofu and skip isoflavone supplements, which don’t behave the same way as isoflavones found in food.

So, what’s the difference between soy and tofu? At its purest, soy is a plant that produces pods full of beans. The pods, called edamame (eh-duh-MAH-may), contain soybeans and are a staple in Asian kitchens. So is tofu, a cheese-like substance made from curdled soybean milk. Since tofu is bland, it picks up flavor from spices, sauces, and other foods. You can buy tofu at the grocery store along with premade soy foods: pre-seasoned tofu, soy cheese, meat substitutes like veggie burgers, and tempeh, a firm and chewy soybean cake that sometimes contains grains and can be cooked much like tofu. (Keep in mind that some premade soy foods can be high in sodium, and check the label.)

There are two main types of tofu: water packed and silken, which differ based on how they’re processed. Water-packed tofu, also called “regular,” must be refrigerated right away. Silken tofu is sealed in an airtight package and only needs to be refrigerated once it’s opened. Each type comes in various textures: soft, firm, and extra firm. “They handle differently,” says Deborah Madison, author of This Can’t Be Tofu. “A firmer tofu is going to hold up better. A soft tofu is going to be very delicate.” Following are the three types you’ll use most often in the kitchen.

Next: Which Tofu Is Best for You?