A badge is a device, patch, or accoutrement which is presented or displayed to annotate some feat of service, a special accomplishment, as a symbol of authority (ex: police), or as a simple means of identification. They are also used in advertising and publicity.
Badges have become highly collectable: in the UK, for example, the Badge Collectors' Circle has been going since 1980 Even today, pin button badges are extremely popular. [http://www.weebadgers.com
In the military, badges are often used to denote qualifications received through military training. Similarly, scouting organizations use them to show group membership and rank.
Members of Fraternities and Sororities often refer to the pins that signify their membership as badges.
One of the best-known badges is the typically star-shaped U.S. sheriff's badge, made famous in Westerns.
The BBC children's program Blue Peter also awards its own "Blue Peter badge" to members of the public who appear on the show.
Case badges are also thick (about 3 mm deep), 3 cm x 3 cm lucite stickers that are often packaged with various computer parts, such as processors and video cards. Modern computer cases are frequently embellished with an indentation on the case's front panel to facilitate the affixing of a case badge. Popular case badges usually come with AMD processors, NVIDIA or ATI video cards, and sometimes with Creative sound cards.
In work places employees are often issued name badges which identify them. Name badges are also commonly issued in high schools and hospitals. They are often used to identify legimate workers from impersonators.