In the early years of computing,
telnet
was used to connect to the command line on remote systems. SSH has
replaced telnet
for remote access needs, and these days when you
hear about telnet
, it is usually when somebody is using the client
as a generic network troubleshooting tool.
That’s because, in troubleshooting sessions, sysadmins turn to
telnet
and
netcat
to
test connectivity to service offerings.
Source: Basic troubleshooting with telnet and netcat,
an article by Dustin Minnich.
Coincidentally, today I used nc
because macOS Mojave doesn't come
with telnet
out of the box.