What are these variables do in Jitsi environment file?

Can you please explain what are these variable functionalities in the .env file of Jitis.

XMPP_DOMAIN,
XMPP_SERVER,
XMPP_AUTH_DOMAIN,
XMPP_MUC_DOMAIN,
XMPP_INTERNAL_MUC_DOMAIN and
XMPP_RECORDER_DOMAIN

Internal for the system strings, used for xmpp addresses.

Can you explain each variable and what will be the value of these variable?

You may check them here: