In many years of computer history,
many processors, operating systems, databases, etc. were constructed and developed.
They are often not compatible with each other
and the program for one system can not be run on the second one.
To take full advantage of computers and the software
the integration is needed ie. data exchange and sharing services.
An example is websites where internet browser
run in a specific system can read pages available on a server in another system.
To make this possible, it was necessary to develop multiple standards and protocols.
For an example TCP/IP, HTTP, HTML are the technologies supported on all systems.