dnsmasq is the default DNS resolver if you use NetworkManager. It runs pretty well most of the time. When it doesn’t, you would not be able to access the Internet if you need to resolve names.
I’m not a fan of dnsmasq, and if you – like me – want to disable it, just edit
/etc/NetworkManager/NetworkManager.conf
and remove/comment
dns=dnsmasq
Restart NetworkManager, it will use traditional faithful method of /etc/resolv.conf.