Splash screen is a display at the ubuntu boot process going on.
If you want to see more details about the ubuntu boot process or just want to turn off the splash screen, you can try the following ways:
1. Edit the grub.
$ sudo gedit /etc/default/grub
Then find the following lines:
delete the words quiet splash
So that later will become like this:
Once finished save and exit immediately.
2. The second step is to update grub.
$ Sudo update-grub
Please restart your computer ..