The splash screen is shown when you boot up ubuntu.
You can stop showing the splash screen and instead view details about your boot process.
Follow the steps below to disable the splash screen.
1. Edit grub.
$ sudo gedit /etc/default/grub
Locate the following line
Remove quiet and splash
Now the line should look like this
Now save and exit.
2. Now update the grub.
$ sudo update-grub