I'm wondering about functional or non-functional requirements. I have found lot of different definitions for those terms and I can't assign some of my requirement to proper category.

I'm wondering about requirements that aren't connected with some action or have some additional conditions, for example:

1. On the list of selected devices, device can be repeated.
2. Database must contain at least 100 items
3. Currency of some value must be in USD dollar.
4. Device must have a name and power consumption value in Watts.

are those requirements functional or non-functional ?