What should you make sure you have with you when you head out to the wilderness? A lot of stuff may prove handy, but perhaps the best checklist to start from for stuff that may get you out of a fix is the 10 Essentials by the Seattle-based Mountaineers group.
This is a version of their systems list which focuses on what the objects need to do rather than specifically which objects you should bring. So, for example, insulation may be warm clothes but could be a wind breaker or waterproofs for snow or rain rather than cold.
Check out Mountaineering: The Freedom of the Hills
I modified it very slightly for space and simplicity. Don’t blame me if you are stuck in the wilderness without the right kit.