Although there is typically only one version available for each API request, some requests have multiple versions, and there may be more in the future.
v query parameter on any resource to access a specific version of the API. For example, to invoke version 1 when retrieving announcements, you could make the following request:
Use of the version parameter is optional unless otherwise indicated in the documentation. If not specified in a request, the oldest non-deprecated version will be used. This way, when a new version is released, current consumers of any of the older versions will not be affected.