Article from Badge Alliance about Digital and Open Badges:
"badge [baj]: a special or distinctive mark, token, or device worn as a sign of allegiance, membership, authority, achievement, etc. (Source: Dictionary.com)
A badge is a symbol or indicator of an accomplishment, skill, quality or interest. From the Boy and Girl Scouts, to PADI diving instruction, to the more recently popular geo-location game, Foursquare, badges have been successfully used to set goals, motivate behaviors, represent achievements and communicate success in many contexts. A “digital badge” is an online record of achievements, tracking the recipient’s communities of interaction that issued the badge and the work completed to get it. Digital badges can support connected learning environments by motivating learning and signaling achievement both within particular communities as well as across communities and institutions. (Source: Erin Knight White Paper)"
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