Can you explain what is meant by the data transfer protocol between systems?

Data transfer protocol between systems is a set of rules and agreements that define how data should be structured, transmitted, and processed during exchange between different devices or programs.

A protocol provides:

• Message format (how to package data)
• Rules for establishing and terminating connections
• Methods for error detection and correction
• Data flow control

For example, HTTP is a data transfer protocol on the internet that defines how clients and servers exchange requests and responses.

Without a protocol, systems cannot understand each other even if physically connected.