A Removable Storage system provides two classes of media pools: system and application. System media pools include free media pools, unrecognized media pools, and import media pools. Removable Storage creates one free, one unrecognized, and one import media pool for each media type in your Removable Storage system.
TIP: keep an extra pair in your pack in case your feet (or your buddy's!) get wet, and on a longer hike change your socks at the top - you will be much more comfortable on the way down. Poly or silk sock liners are also a great treat on those longer hikes to help prevent friction burns (aka blisters!).
Backpacks are for carrying stuff that you don't need until you reach your campsite, like cooking gear and tent pegs. Backpacks are not for carrying anything you need as you're walking around, like cameras or lenses. Bag makers sell a lot of expensive packs to a lot of people new to the hobby. Don't fall into this trap.