A buckle (from Latin buccula) is a clasp used for fastening two things together, such as the ends of a belt, or for retaining the end of a strap. Before the invention of the zipper, buckles were commonly used to fasten boots and other shoes.
The roller buckle is a mid-20th century invention; buckles with multiple prongs had already appeared in the 18th century.
Buckles can also be seen on backpacks, watches and other wrist jewelry, or for ornamental purposes on other various objects. Buckles are also commonly seen in modern gothic fashion.
Buckles of completely different design, buckles usually made of plastic that fasten onto a strap in two places and clip together, are increasingly used.
A buckle can refer to a seat belt or safety belt, as in the term, "buckle up." This originally military phrase from the cavalry refers to strapping the saddle to a riding horse, which means "get ready for departure".