JSON (JavaScript Object Notation) is a lightweight, human-readable data-interchange format. It is widely used for transmitting data between a server and web applications, as well as for configuration files and data storage. JSON is based on a subset of the JavaScript programming language, but it is language-independent and can be used with various programming languages. It uses a simple text-based format consisting of key-value pairs, where keys are strings enclosed in double quotes and values can be strings, numbers, booleans, arrays, or other JSON objects. Its simplicity and ease of parsing make it a popular choice for data serialization and exchange in modern web development and beyond. JSON is often preferred over XML due to its smaller size and easier readability.