WebEngine has three options for rendering output to work with different data access styles, which are called modes. Modes only affect WebEngine.
If you are building HTML experiences solely on Zesty.io and want to guard against people accessing your content outside of the HTML document, traditional is right. GET APIs that expose content need to be turned on manually, giving teams the options to turn on some items but not others. Custom JSON or other data format endpoints made with Parsley can still be made without an affect on access.
Hybrid is best of both worlds. Pages still render HTML at their routes, but they can also render JSON with a simple get parameter. For example
/about/would return HTML, but
/about/?toJSONwould return a fully hydrated JSON object of the about page.
Mode is controlled by a setting that can be found in the Manager UI under General. The default mode is always "traditional".
Setting editable under "general"