you need to know the following:
What these computers are and what is inside them?
In the picture you see three things. First is different types of computers like mobile, desktop, tablet, etc., In the second one there are computer accessories which are optionally or mandatory needed to operate a computer of particular type. The pencil accessory is used for handwriting or drawing stuff. The third one is list of applications softwares which run in one or more of the different computer types. More are there