What are REST and SOAP, and how do they differ?

REST (Representational State Transfer) and SOAP (Simple Object Access Protocol) are two different approaches to organizing interaction between a client and a server.

REST:

• An architectural style that uses standard HTTP methods (GET, POST, PUT, DELETE).
• Works with resources identified by URLs.
• Lightweight, typically uses JSON or XML for data transfer.
• Does not require complex protocols, easier to implement and scale.

SOAP:

• A message exchange protocol based on XML.
• Uses its own message format and security standards, transactions.
• More formal and strict, supports extended features (e.g., WS-Security).
• Often used in enterprise systems where reliability and security are important.

Differences:

• REST is simpler and lighter, SOAP is more complex and formal.
• REST uses standard HTTP methods, SOAP uses its own XML messages.
• REST is more flexible and scalable, SOAP is more reliable and standardized.

Example of a REST request:

GET /users/123 HTTP/1.1
Host: example.com

Example of a SOAP message — XML with a specific structure and headers.