What is "xrds"

XRDS (eXtensible Resource Descriptor Sequence) is an XML format for discovery of metadata about a web resource – in particular discovery of services associated with the resource, a process known as service discovery. For example, a website offering OpenID login can resolve a user's OpenID identifier to an XRDS document to discover the location of the user's OpenID service provider.

XRDS, formerly Crossroads, is the flagship academic magazine for student members of the Association for Computing Machinery or ACM. Issues focus on computer science topics and are published quarterly in both print and electronic forms. The magazine is distributed to tens of thousands of students worldwide. The full text of every issue is available online to ACM members through the ACM Digital Library, with many articles selected by the editorial staff open to the general public. The first edition was published in 1994 and was ACM's first electronically produced publication, originally being distributed in HTML. It is run by a group of volunteer students and supported by staff at ACM headquarters in New York City. XRDS employs a mixed invited and unsolicited submissions model, which are refereed by a staff of permanent editors.. Issues exist for every quarter since Fall 1994, with a few extra, mid-Summer, issues .