Sardines pilchards, are a group of several types of small, oily fish related to herrings, family clupeidae. Sardines were named after the Mideterranean island of Sardinia, where they were once in abundance.
The terms are not precise, and the usual meanings vary by region; for instance, to many people a sardine is a young European pilchard. A generalization is that if the fish is under 4” long (10 cm) it is classed as a sardine, and if larger than 4” it is classed as a pilchard.
As a food, sardines are very rich in minerals. They can be consumed in a variety of ways (e.g., grilled, smoked) though canned sardines are very popular worldwide.