Chicken stock (though there is a slight difference).
To make chicken broth, you simmer fresh chicken meat (and sometimes bones), carrots, onions, celery, and a few aromatics, such as parsley, thyme, and peppercorns. A few cloves of garlic and bay leaf might also be added. Once strained, this flavorful liquid can then be used to make soup and much more.
Chicken broth is used in sauces, braises, gravies, and to cook rice. A little can deglaze a pan or moisten pasta. Homemade broth is usually preferred, but the store-bought variety is more convenient for most people.
Broth and stock are often used interchangeably, but they aren't exactly the same; stock makes greater use of bones. Though broth is sometimes made with meat still on the bone, broth's distinguishing flavor comes from the meat itself. Compared with stock, it has a lighter body and a more distinctly meaty (or vegetal) flavor. Broth is more or less ready to eat while stock usually needs more enhancement.
Substitute chicken stock; vegetable broth, and, in some cases, water. A reconstituted bouillon cube can work in a pinch, too.
Your best bet for selecting store-bought chicken broth is to sample a few varieties. Look for an authentic chicken flavor, subtle vegetal notes, and a rounded consistency. Choose a low-salt option if available, which gives you better control over the saltiness of the finished dish.
If using homemade broth, taste the broth; if you'd prefer its flavor to be more concentrated, simmer it until it's as flavorful as you like. Depending on how you'll be using the broth, you may want to season it with more salt at this point. If the broth is very fatty, chill it and then remove the solidified fat with a slotted spoon. Most store-bought broth can be used right from the package. Be careful when reducing store-bought broth; it will become more concentrated but so will its saltiness.
Unopened broth will keep for a year at least in a cool, dry place. Once opened, it will last up to a 5 days in the refrigerator; date opened packages. Broth will keep for months frozen. It's a good idea to freeze it in different amounts so you can defrost just what you need.