REST (Representational State Transfer) is a software architectural style for distributed systems that is based on the principle of stateless resource manipulation. REST APIs use HTTP verbs (GET, POST, PUT, DELETE) to perform operations on resources (e.g., users, products, orders).
SOAP (Simple Object Access Protocol) is a messaging protocol for exchanging XML-encoded data between applications over a network. SOAP APIs typically use HTTP as the transport protocol, but can also use other protocols such as SMTP or JMS.
JSON (JavaScript Object Notation) is a lightweight data-interchange format that is easy for humans to read and write. JSON is often used to represent data in REST APIs.