A Visual Display Unit (VDU) is a computer monitor that is used to display the output from a computer. It is an electronic device that displays text and images on a screen.
On the other hand, computer printing is the process of creating a hard copy of the data stored in a computer by using a printer. A printer is an external device that connects to a computer or other electronic device and is used to produce a physical copy of digital data, such as text, graphics, and images.
In summary, a VDU is a device used for displaying the output of a computer, while a computer printer is an external device used for creating a hard copy of the data stored in a computer. In functionality, a VDU is used for visualizing the output of the computer, while a printer is used for creating a physical copy of the data.