.lan is widely used (by OpenWRT and Ubiquity and likely others) by home / SMB routers, where all connected devices will automatically be assigned hostname.lan. Technically, .home.arpa and/or .internal are designated for this, but .home.arpa is pretty clunky and they're very new (.home.arpa is from 2018 and .internal from 2024). Usage of .lan for this predates either.
.lan is widely used (by OpenWRT and Ubiquity and likely others) by home / SMB routers, where all connected devices will automatically be assigned hostname.lan. Technically, .home.arpa and/or .internal are designated for this, but .home.arpa is pretty clunky and they're very new (.home.arpa is from 2018 and .internal from 2024). Usage of .lan for this predates either.