A REST API (Representational State Transfer) is a set of rules and conventions for creating and using web services that facilitate communication between different applications. By using standardized methods such as GET, POST, PUT, and DELETE, a REST API allows systems to manipulate resources (data) via HTTP requests. Data is typically exchanged in JSON or XML format. This enables various applications—whether web-based, mobile, or backend services—to communicate and interact in a coherent and scalable manner. REST APIs are essential for integrating services, automating processes, and enhancing interoperability across different platforms. By structuring endpoints and responses logically and uniformly, REST APIs simplify the development and maintenance of connected systems.