What Are All Straps on a Backpack Used For?

https://mountainsforeverybody.com/what-are-all-straps-on-a-backpack-used-for
There are at least five types of straps on a backpack:
Straps used for gear attachment only.
Straps with dual use for the pack compression and gear attachment.
Straps used for comfort and packs stabilization.
Harness straps.
Straps used to close the pack.
All of them are discussed here.