Sometimes could be useful to get automatic access to your Ubuntu box.
Imagine you want a default user that can access the Inernet, You could create the user with the specifics authorizations then with the autologin nobody of the users of your Ubuntu box needs to authenticate.
There are two ways you can follow. The first is for those who like the command line interface:
The command line interface way
1. open a new terminal
2. open the /etc/lightdm/lightdm.conf configuration file with an editor (my favourite one is vim)
$ sudo vim /etc/lightdm/lightdm.conf
3. at the end of file add the following two lines:
The GUI way
1. Open the "System Settings" application
2. Select "User Account".
3. Select the user you want to autologin.
4. Click on the "Unlock button".
5. Move the "Automatic Login" switch to the position you want