Screen size is the diagonal measurement of a tablet’s display in inches.
A tablet display's pixel density in Pixels Per Inch (PPI). All else equal, a higher PPI means a higher resolution screen.
The raw amount of power which a tablet's battery can hold.
Hours of battery life with typical use. This is closely related to how the tablet is being used. Reading a book with an e-reader app will drain much less battery life than playing a 3D game, for example.
Internal storage, or the amount of space for users to store their files on a device. These figures represent the storage for the base model of a device. Often, manufacturers will have more expensive options which have higher storage capacities.