JSON (JavaScript Object Notation)
Definition
A lightweight data interchange format that is easy for humans to read and write and easy for machines to parse and generate.
JSON is a text-based data format derived from JavaScript syntax that has become the standard for data exchange on the web. It supports six data types: strings, numbers, booleans, null, arrays, and objects (key-value pairs). Its simplicity and universality make it the preferred format for APIs, configuration files, and data storage.
JSON replaced XML as the dominant data interchange format because of its lighter syntax and native compatibility with JavaScript. Virtually every programming language has built-in or standard library support for parsing and generating JSON.
Common uses include API request and response payloads, configuration files (package.json, tsconfig.json), NoSQL database storage (MongoDB), and local storage in web applications. JSON Schema provides a way to validate JSON data structure, while JSON Web Tokens (JWT) use JSON as the payload format for authentication tokens.
Related Calculators
Related Terms
API (Application Programming Interface)
techA set of rules and protocols that allows different software applications to communicate with each other and share data or functionality.
REST API
techAn architectural style for web services that uses standard HTTP methods to create, read, update, and delete resources, providing a stateless communication interface.
CSV (Comma-Separated Values)
techA plain text file format that stores tabular data using commas to separate values and newlines to separate rows.
JWT (JSON Web Token)
techA compact, URL-safe token format used for securely transmitting information between parties as a JSON object, commonly used for authentication.
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