What is the primary purpose of JSON?

The primary purpose of JSON (JavaScript Object Notation) is to facilitate the transmission of data between a server and a web application. JSON is a lightweight data interchange format that is easy for humans to read and write, and easy for machines to parse and generate.

When web applications need to communicate with servers, they often send and receive data in a structured format that both the client and server can understand. JSON serves this role effectively due to its simplicity and compatibility with various programming languages, especially JavaScript, which is commonly used in web development.

By using JSON, developers can transmit structured data, such as objects and arrays, in a format that can be easily processed. This capability is critical in web applications for tasks such as fetching data from a server or submitting user inputs, thus enabling a dynamic and interactive user experience.

Other options pertain to different aspects of software development. Creating complex user interfaces generally involves frameworks or libraries designed for UI development, not directly related to data transmission. Storing data in a database involves persistent storage solutions that may use different formats or methodologies. Encrypting sensitive information is a security measure that focuses on protecting data, rather than the format used for data interchange.