Category is used to import or update Categories
Category supprots ID or Name as entity key.
Your entity key must be unique. If you have two categories with same Name fields, you will not be able to use Name as entity key.
Altohugh category has many different column destinations, we would describe only ones that have special functionality.
All other column destinations do not support inputing multiple values in one cell, and they don't support using multiple columns as well.