An Open Badge is a PNG or SVG image file that invisibly incorporates “metadata” in JSON (JavaScript Object Notation) or JSON-LD (JSON for Linked Data) format.

Open Badge Version 1.0 was launched in 2013 in the US, thanks to the ‘Clinton Global Initiative: Better Futures for 2 Million Americans Through Open Badges’. In a single year more than 2 Million American Students and workers have been certified with Open Badges.

In 2015 version 1.1 has been released, which brought minor changes to the Open Badge format. This changes allowed the Badge Issuer to ‘extend’ the badge adding additional metadata in JSON-LD format.

Version 2.0 was released in January 2017and then updated in April 2018. This update specifies that the data embedded in the badges have to be in JSON-LD format. This release also introduces a set of new features:

• Badge Endorsement – a badge that has been issued to a group of people (badge class) can be approved (endorsed) by a third Party. As an example, a badge issued by a tutor can afterwards be endorsed by the School.
• Person Endorsement – a badge that has been issued to a person (assertion) can be endorsed by a third Party. As an example, the colleagues of a Badge recipient can endorse the specified skills of the recipient, giving the badge a higher value in the time.
• Criteria Embedding – the criteria for assigning the badge (exams to be taken, etc.) can be incorporated directly into the badge, whereas previously, the issuer had to provide a hypertext link to a URL on which the details of the criteria for the achievement of the badge where stored.
• Tests Description Embedding – the badge can also incorporate a detailed description of the tests passed by the holder to prove the possession of the criteria required to earn such a badge.
• Full portability – as all the relevant information can be embedded in the badges, those information are always available without the need for external links that could become broken with the time. As an example the Badges Issuer can cryptographically sign all metadata associated with a badge. Doing so simplifies the badge’s verifiability and, very important, the recipients of a badge will never have an ‘incomplete’ badge should the issuing platform cease to exist.
• Internationalization – version 2.0 introduced the ability to publish multi-language badges.
• Version Control – it is possible to update badges and track the differences through the different versions.
• Image Information Embedding – Open Badges0 can include information about the images that represent them, making them more readable by machines.
• Assign badges to non-email identities – badges can be issued for non-email address identities such as for verified social profile credentials.
• Better alignment – in version 1.0 was already allowed to issue a badge making reference to a URL to a framework or a standard which the badge aligns to; version 2.0 allows to issue a badge referring to multiple frameworks and standards.