Cracked wheat is whole kernels of wheat that have been coarsely cracked, so that each piece ends up being about 1/4 of the size of the whole kernel. (In case you’re thinking, cracking wheat must make shelling peas seem interesting, it’s actually rollers that do it, not people.) The cracked kernels are then sold as is for cooking use.
Cracked wheat can be made in four different grinds: fine, medium, coarse, and very coarse. The grind will depend on the producer of it and what market they are making it for.
Cracked wheat is used in breads, non-traditional risotto recipes, salads, muffins, pancakes, etc. You only use a small portion of cracked wheat in breads, as the shards are “sharp” (not as though they’d cut you or anything), but sharp enough to cut through the gluten which is supposed to trap the gas from the yeast and make the bread rise.
You can even cook it up to use as a side dish, as you would rice or bulgur wheat. But you’ll want to jazz it up, probably, by cooking it in a broth, with some herbs, veg or onion.
Bulgur wheat starts as cracked wheat, but goes a few steps further. See separate entry on bulgur wheat.
Many recipes that have “cracked wheat” in the title actually use bulgur, perhaps because “bulgur” is still quite an exotic word to the average consumer in English-speaking countries.
These days, cracked wheat for many generally means cracked wheat bread. But it is used in many other parts of the world in savoury dishes, as rice would be. To cook on its own, boil 1 cup (4 oz / 120 g) of cracked wheat in about 2 1/4 cups (18 oz / 530 ml) of liquid for around 40 minutes.
1/2 cup coarse cracked wheat, dry, uncooked = 2 oz / 60 g
1/2 cup coarse cracked wheat, cooked = 3 oz / 85 g
1 cup fine cracked wheat, dry, uncooked = 150 g = 325 g uncooked but soaked
Sometimes in Middle Eastern recipes “burghul” is translated as “cracked wheat”. You’ll know that what they mean is actually “bulgur wheat”, if they talk about soaking the grain, but not boiling it.