A JSON schema is written in JSON syntax and will be saved typically in a file with a .json extension. It is indicated as a JSON schema by the $schema keyword, which should be the first keyword of the top-level object and have a value of: "http://json-schema.org/draft-N/schema#" or "http://json-schema.org/schema#".
In the first example above, the schema version is explicitly named, with version names having the form draft-04, draft-06, etc. If the version name is omitted, as in the second example above, then this indicates that the schema version to be used is the latest version (currently draft-07).
In JSON Schema View, you can change the version in the combo box in the bar at the top of the main window (see screenshot below).
If you use a feature of a newer schema version and then switch to an older version that does not support this feature, then the following happens:
•A message appears asking whether you wish to remove/convert the feature or keep the feature
•If kept, the new feature's corresponding component or detail is shown in an orange text color. For example, if a value has been set for the const keyword (new in draft-06) and you switch the schema version to draft-04, then the value of the const keyword is displayed in orange.
For information about the JSON Schema specifications, especially about additional features with each version, see the links below:
JSON Schema specification: http://json-schema.org/specification.html
Draft-06 release notes: http://json-schema.org/draft-06/json-schema-release-notes.html
Draft-07 release notes: http://json-schema.org/draft-07/json-schema-release-notes.html