JSON (JavaScript Object Notation) is a lightweight data-interchange format, easy for humans to read and write, and easy for machines to parse and generate. It is based on a subset of the JavaScript Programming Language spec.

Intro to JSON at - JSON

A JSON overview

Import the basic functions in TouchDesigner in a script: import json

JSON is closely tied to python dictionaries. See:

There are JSON functions specific to TouchDesigner. TDJSON goes to/from TouchDesigner objects.