A sequin is a small, shiny disc sewn onto clothing or costumes to make them sparkle and catch the light. Sequins are usually made of plastic or metal and come in different colors, though silver and gold are most common.

When someone moves while wearing sequined fabric, the tiny discs shift and flash, creating an eye-catching shimmer. You'll often see sequins on fancy dresses, dance costumes, or stage outfits where performers want to stand out under bright lights. Ice skaters, ballroom dancers, and musicians frequently wear sequined costumes because the sparkle helps them command attention and adds excitement to their performances.

Sequins became wildly popular in the 1920s when fashion designers started using them on glamorous evening gowns. Today, you might find them on everything from holiday decorations to backpacks with reversible sequins that change color when you brush your hand across them.

Sewing hundreds or thousands of sequins onto a single costume takes enormous patience and skill, which is one reason sequined outfits can cost more than regular clothes.