The Hershey bar (officially called "The Hershey's bar" by The Hershey Company) is the flagship chocolate bar introduced in 1900 (marketed as "The Great American Chocolate Bar") manufactured by the The Hershey Company, invented by Milton Hershey. Hershey bars are available in six regular editions: Milk Chocolate, Milk Chocolate with Almonds, Special Dark Chocolate, Cookies 'N' Creme, Mr. Goodbar, and Krackel. There were also 6 limited editions: Double Chocolate, Nut Lovers, Twosomes Reese's Pieces, Cookies 'N' Chocolate, Twosomes Heath, and Twosomes Whoppers.

Recently, the Hershey Company introduced a line of Extra Dark chocolate bars with 60% cocoa solids content. The three varieties are solid chocolate, chocolate with macadamia nuts and dried cranberries, and chocolate with cranberries, blueberries, and almonds. Hershey's marketing emphasizes the antioxidant qualities of these bars' ingredients, although the actual candy's value as a health food is questionable.

Hershey Milk Chocolate and Milk Chocolate with Almonds and peanuts were both introduced in 1894. All ten editions have between 210 and 230 calories per bar.

All ten editions also have an OU Kosher status, which means they are approved by the Kashruth Division of the Union of Orthodox Jewish Congregations of America.

The Hershey chocolate process was developed by Milton Hershey and was the first mass-produced chocolate in the United States. As a result, the Hershey flavor is very widely recognized in the United States but less so internationally, in particular those areas where European chocolates are more widely available.

Currently, the largest Hershey's bar commercially available weighs 5 pounds and costs US$35 on Hershey's website.