The JSON API Plugin is a component available since the Thorium Builder 1.1 version.
This plugin is a little bit technical, but it simplifies a lot the process of working with a JSON File or calling an external API Rest.
Read the definition of an API Rest at Wikipedia: Representational State Transfer
Using JSON Files or JSON Api is useful when you want to display data managed in an external database that implements a JSON API Rest
JSON Files (JavaScript Object Notation) is an open-standard file format that uses human-readable text to transmit data objects. See definition on Wikipedia: https://en.wikipedia.org/wiki/JSON
In order to use the JSON Plugin, you must go to your project settings=>Plugins and enable the Json API Plugin:

Since the version 2, you can setup the options and headers used by the API, for more details, read the documentation Setting up a API Rest source
The Json API plugin lets you display Remote data in various ways, you can learn what’s possible in this help page: Json API WorkFlow
There are several Widgets available with the Json API Plugin:
JSON Repeater. The JSON Repeater lets you display a set of Data (Client List, Product List …) provided but the API.
Read the JSON Repeater Documentation
The JSON Repeater can be populated from a JSON static file or from a remote Json API Rest.
JSON Search Box. The JSON Search Box is associated to a JSON Repeater and lets you search for a value within the Repeater Memory Data.
Read the JSON Search Box Documentation
JSON Action Button. The JSON Action Button has 2 functionalities: if it is added to the PWA layout linked to a repeater, you can call an API with different parameters and reload the Repeater with specific search options.
If the Action Button I placed inside a line of a Repeater with a Custom template, then it can call another page by passing the line data and primary key (ID).
Read the JSON Action Button Documentation
JSON Displayer. The JSON Displayer lets you display a Record loaded from a JSON Repeater or from an API that returns a single Record.
Read the JSON Displayer Documentation
JSON Fields. The JSON Fields represent record field content and can be placed into a Repeater or within a JSON Displayer.
Read the JSON Fields Documentation
JSON Form. The JSON Form widget lets you create a User Form where users will be able to enter data and send them to a remote API (for inserting data to a DB in general).
Read the JSON Form Documentation

JSON Repeater

JSON Displayer
The Json API Repeaters & Displayers are using the fetch API ( https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API )
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