Bell pepper is a cultivar group of the species Capsicum annuum. Cultivars of the plant produce fruits in different colors, including red, yellow, green and orange. Bell peppers are sometimes grouped with less pungent pepper varieties as "sweet peppers". Peppers are native to Mexico, Central America and northern South America. Pepper seeds were later carried to Spain in 1493 and from there spread to other European and Asian countries. Today, Mexico remains one of the major pepper producers in the world.

The misleading name "pepper" (pimiento in Spanish) was given by Christopher Columbus upon bringing the plant back to Europe. At that time peppercorns, the fruit of Piper nigrum, an unrelated plant, were a highly prized condiment. Bell peppers are botanically fruits, but are generally considered in culinary contexts to be vegetables. When cut off, the top of the bell pepper is referred to as a "pepper pan".

The term "bell pepper" or "pepper" or "capsicum" is often used for any of the large bell shaped capsicum fruits, regardless of their color. In British English, the vegetable is simply referred to as a "pepper", or additionally by colour (as in the term "green pepper", for example), whereas in many Commonwealth of Nations countries, such as Australia, India, Malaysia and New Zealand, they are called "capsicum". Across Europe, the term "paprika", which has its roots in the word for pepper, is used—sometimes referred to by their color (e.g., "groene paprika", "gele paprika", in Dutch, which are green and yellow, respectively). Paprika also refers to the powdered spice made from the same fruit. In France it is called "poivron", with the same root as "poivre" (meaning "pepper"), or "piment". In the United States and Canada, the fruit is often referred to simply as a "pepper" or referred to by color (e.g. "red pepper", "green pepper"), although the more specific term "bell pepper" is understood in most regions. In parts of Indiana, and Pennsylvania, the fruit is called a "mango".