Why do things look fuzzy/pixelated on my screen?
This can happen because the display resolution that you have set it is not the right one for your screen.
To solve this, click the icon at the very right of the menu bar and go to System Settings. In the Hardware section, choose Displays. Try some of the Resolution options and set the one that makes the screen look better.
When multiple displays are connected
If you have two displays connected to the computer (for example, a normal monitor and a projector), the displays might have different resolutions. However, the computer's graphics card can only display the screen in one resolution at a time, so at least one of the displays might look fuzzy.
You can set it so that the two displays have different resolutions, but you won't be able to display the same thing on both screens simultaneously. In effect, you will have two independent screens connected at the same time. You can move windows from one screen to another, but you can't show the same window on both screens at once.
To set up the displays so that they each have their own resolution:
Click the icon at the very right of the menu bar and select System Settings. Open Displays.
Uncheck Mirror Displays.
Select each display in turn from the gray box at the top of the Displays window. Change the Resolution until that display looks right.