What are channels in an audio recorder software?

I compiled and ran this audio recorder program derived from JUCE: https://gitlab.com/DamienAuvray/simpleaudiorecorder

I can see that it has the options of selecting channels. I am a newbie in this area.
What do those channels represent? Do they represent different microphones? Selecting many channels means that we can use more than one microphone for recording?

Please explain.

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A ‘channel’ is a single mono input or output. The meaning of a given channel is device dependent, ie. you might have an audio interface provides multiple mono i/o’s, or you might have something like the default audio subsystem, which usually provides mono in (mic) and a stereo out (speakers/headphones).