re: Rooting questions (Galaxy S5) UPDATE: rooting complete

Rooting gives you a higher level of rights to do things with your phone. There are some apps that require root access to run. Rooting does not remove bloatware automatically. You can run apps that will "freeze" the bloatware so that it does not run. Before you uninstall or freeze any system apps (including bloatware) you should check to make sure that it is safe to do. The XDA forums is a good place to check for a phone specific thread about what system apps are safe to freeze or uninstall.