What Should I Consider Before Buying a Backpack? (Revealed)

https://outdoorsfaqs.com/what-should-i-consider-before-buying-a-backpack/
If you are in the process of buying a backpack, here are the criteria you might want to consider, given in no particular order:

Capacity or volume.
Versatility.
Comfort.
Essential features.

All of them are discussed here.