The formats, codes and procedures that manage the exchange of data between two locations. The format is the layout of the data, the codes are the commands that cause actions to take place, and the procedures are how and when these elements interact with each other. See
talk.
All networks and communications systems follow a protocol. For example, TCP/IP is the network protocol of the Internet as well as nearly every home and office network (see
TCP/IP). In the crypto world, the blockchain protocol is the procedure that nodes around the world follow to communicate with each other to validate transactions (see
blockchain protocol).
Protocols and APIs Are Similar
A protocol is like an API (application programming interface), which also defines the format, codes and procedures. However, protocols commonly refer to communications systems, whereas an API is an exchange between the OS and an application or between an application framework/platform and the programs that interact with it (see
API). See
application framework.
From "Protokollon"
The term comes from the Greek "protokollon," which was the cover page to a manuscript that provided a description of the contents. See
communications protocol,
protocol stack and
OSI model.