How logging in helps computer users?

Logging in lets the computer know it's you, and helps the user in two major ways. First it sets up all your settings, your screen saver, desktop background, and any other likes and dislikes that you want to personalize the way you like it so that you have a better experience. The other major thing logging in does is organize your files and data into your own personal location on the hard drive. For instance your pictures are in your Pictures folder while another users pictures are in their pictures folder. Same with movies, music, and any other files and data.