JSON (JavaScript Object Notation): JSON is a lightweight data-interchange format that is easy to read, write, and parse for both humans and machines. It is a popular format for transmitting data between a server and a client, as it is more compact and efficient compared to other formats like XML. JSON is most commonly used in web applications as it integrates easily with JavaScript and other programming languages. It represents data as key-value pairs, making it an organized and structured way to store and exchange data.