Once my computer has started, prompts me to log in. The login manager that I use is LightDM (However, in my days using arch linux, I used a script that automagically started X using .xinitrc when I log into tty1. That script went into .bashprofile). There isn’t much to say about a login manager because it’s pretty common. It asks for a username and a password. Then lets me choose a Xsession to log into.