(WHTM) – Grocery stores package foods in many different ways, but they also have many ways to indicate when foods may be past their prime.

While some say “use by” a specific date, others say “sell by” the posted date. But what is the difference?

According to the University of Connecticut (UConn), food dating is not required by federal law. The only exception to this is infant formula and some baby food. For all other foods, except for dairy products in some states, dating is up to the manufacturer.

Stores are also not legally obligated to remove outdated products from their shelves, UConn reports. This means that consumers should always check the packaging to make sure what they are buying is the freshest.

There are a few terms that consumers should be aware of when it comes to food dating, some of which can be confusing. Here are some common terms you may see while shopping for food.

  • Expiration date: Food should be thrown away after this date, as it may no longer be safe to eat.
  • Use-by or Best-used-by date: This is a suggestion on when the food should be used to ensure the best quality. It generally is safe to consume food that is past this date, but the quality may suffer. These phrases are mostly found on canned goods, dry goods and other shelf-stable items. According to UConn, the FDA is supporting the food industry’s effort to standardize its use.
  • Sell-by date: According to the USDA, this date indicates when the item should stop being displayed for sale. Items with this phrase are generally safe for consumption after this date, but the food may lose flavor and eye appeal.

UConn offers some tips for certain foods that can be consumed after their posted date, such as milk or eggs, on its website. But consumers should always judge by a product’s odor, texture or appearance before consuming any foods suspected to be expired, the USDA advises.

In other words, if you feel like it’s going bad, don’t take the risk — and don’t eat it.