From Fedora Project Wiki

Chapter 2: Login

This chapter describes how to login to your new Fedora KDE 4 desktop. To login to your desktop you will need system user account and password. If you don't have any account yet, you should ask system administrator of your system to create it or add new one yourself (see Administration Guide - User Accounts chapter). If you have forgotten your user account, your password, or both, read the section I Cannot Login: HELP!. This chapter assumes you are using KDM display manager (see Installing KDE section of KDE wiki page).

Image:kdm_login_screen.png