Protocol

A protocol is a set of rules (specifically an industry standard) that formats all the data that goes over the network (ie: header, endianness, byte size, ...)

"A networking protocol defines the format of the information and rules needed for two devices to communicate."

Back in the day ...

The problem back in the day was that IBM, HP, ... all had different protocols that couldn't talk with one another. In the 70s and 80s we made these standards so that pieces of equipment between companies would work.

We want to do:

Error detection
Encryption
Error Correction