JSON

JSON is a lightweight, text based format for storing and exchanging structured data between systems. It gives computers a simple, universally understood way to represent information such as a customer record, a product listing, or the settings for an application, using plain text that both humans and machines can read. When two pieces of software need to pass data to each other, whether a browser talking to a server or one service calling another, JSON is very often the language they use to do it.

Its structure is built from a small set of pieces that combine cleanly. Data is organized as key and value pairs grouped inside curly braces, forming objects, and as ordered lists inside square brackets, forming arrays. Values can be text strings, numbers, the booleans true or false, null for the absence of a value, or nested objects and arrays, which lets JSON describe deeply layered information. A single product, for example, might be an object with keys for name, price, and availability, and a catalog would be an array of such objects. Because the format is just text following these consistent rules, virtually every programming language can read JSON into its own native data structures and write those structures back out as JSON, which is exactly why it became the common tongue of data exchange.

The name is an acronym for JavaScript Object Notation, and the format was specified by Douglas Crockford in the early 2000s. It grew out of the way JavaScript already described objects, but it quickly outgrew that origin. Despite the JavaScript in its name, JSON is entirely language independent today and is used far beyond the browser, in back end services, mobile apps, configuration files, and databases. Its rise came partly as a reaction to older, heavier formats like XML, since JSON conveyed the same information with far less clutter and was easier to read and parse.

For a business, JSON matters because it is the plumbing behind almost every modern digital integration. When your website pulls in reviews, your store syncs orders with a fulfillment service, or your analytics platform receives event data, that information is very likely traveling as JSON. Its simplicity means integrations are faster to build and cheaper to maintain, and its ubiquity means nearly any tool you adopt will speak it. That interoperability lowers the cost of connecting systems and reduces the risk of being locked into one vendor's proprietary format.

A few nuances are worth knowing. JSON is strict about its syntax: keys and string values must use double quotes, trailing commas are not allowed, and comments are not part of the standard, which trips up newcomers who treat it like relaxed JavaScript. It is a data format, not a programming language, so it holds information but contains no logic. JSON also relates closely to several adjacent concepts. It is the usual payload carried by webhooks and returned by APIs, it underlies schema markup that helps search engines understand page content, and typed languages such as TypeScript often define shapes that describe the JSON a program expects. Understanding JSON is fundamental to understanding how modern software components share information.