Tents are essential for long term survival.

There are 3 item types of items that can go in tents:
Backpacks
Weapons & Tools (All tools including Night Vision Goggles and Binoculars. All weapons including Sidearms).
General items (p.e. ammo, vehicle parts, Blood Bags etc.).
A tent can hold a fixed amount of each item-type, within the item-type each item counts as one (unlike in the Inventory system).
A tent can hold up to five backpacks, ten weapons & tools and fifty general items. For example one tent can hold five binoculars, five M4A1s, forty STANAG mags, ten engine parts and five backpacks at the same time.
Tents require 3 Inventory slots and can be placed in Backpacks.
Tent placement:
As of now the tent placement seems to be very bugged. Though, the following steps seem to fix most of these problems:
Crouch and enter first person view, look at the ground ahead of you, press G to open your gear and try to place the tent. It wont work the first time, so move back a little step using your S key and try again while your gear window is still open. Try this like 5-10 times, works!
It is possible to place tents very close to trees, even under them, also, the area doesn't have to be perfectly flat. Be advised though, that as of version 1.7.2.6, placing the tent very close to a tree may cause it to lose all player interaction options.

[youtube]http://youtu.be/xMcatWhm9BU[/youtube]

We have added two general storage tents that are for everyone's use for leaving and taking needed supplies. Please add more than you take!

They are to the left of the command barracks, next to the drinking well. The one closest the barracks is for medical and food supplies, the one closest the well is for mechanical, weapons and misc gear.