Since we all have different expectations of what hiking and backpacking should be this hiking checklist will either seem like over-kill or very light at least until you load your pack. Please use it only as a starting point. If you're new to hiking ask a guide for recommendations.
Plan ahead. If you have to spend an extra night in the backcountry because of an emergency are you prepared.
Be honest with yourself. Are you ready for what you're attempting to do? If someone is planning to hike the Overland Track straight-through and they've only been walking 5 miles a day in walking shoes, they're going to be exhausted when they add 30-80 pounds of hiking equipment to their pack. Throw in new boots that have yet to be broken-in and they'll be down for the count. Play it safe and talk to others who have done what you plan to do and plan out a training schedule ahead of time.
Consider what you might encounter on your hike (i.e. animals, insects, plants, etc.) and plan accordingly.
The following list is an extensive one but by no means exhaustive. Obviuosly for an hour's hike you wont need most of this, but even its only a full day hike be prepared for something to go wrong or off track, and having to spend the night outdoors until daylight comes back around.
1. Extremely Important
Give someone a copy of your written daily schedule and where you expect to be in case of emergency. Hopefully you'll never need it, but if you do rescue teams will know where to look, as opposed to nobody even knowing you're missing.
2. Shelter, etc.
___Backpack/day pack/hydration pack
___Camping tent or shelter
___Water filter and/or purification tablets
___Camp stove and fuel
___Food (bring extra) - freeze dried a good option
___Folding knife or multi-tool
___Small can opener
___Fleece jacket or two
___Hiking socks/extra hiking socks
___Pants/convertible pants with zip-off legs/shorts
___Rain gear (a poncho thats works as a pack cover might do)
___T-shirt (wicking, avoid cotton)
___Cell/Satellite phone/emergency beacon (consider where you'll be)
___Compass or GPS (Global Positioning System)
___Extra prescription glasses if required
___First aid kit (tweezers, moleskin etc. for blisters)
___Flashlight/headlamp and batteries
___Lighter/fire starter/waterproof matches
___Survivabl kit such as the Bear Grylls ultime kit
___Rope/twine/clothes line (i.e. suspend pack 10 feet overhead away from animals)
___Small hand shovel (i.e. fires, toilet pit, etc.)
___Soap/hand sanitizer (non harmful to environment such sea to summit wilderness wash)
___Space or emergencey reflective blanket
___Tent/gear repair kit
___Ziplock bags (to help keep gear dry)
___Tarp or groundsheet