There is a backpacking equation that you must remember when packing. The more you carry, the happier you will be at night. The less you carry, the happier you will be during the day. To achieve a minimum level of comfort at night, you will need a sleeping bag, a sleeping pad, and probably a tent. These things vary depending on the climate and conditions where you will be camping. A hammock is another sleeping option. A mosquito net can be useful. An inflatable pillow will increase your comfort level. A book and a candle are good for relaxing in the evening.
Unless you are embarking on a serious mountaineering expedition, avoid expensive and trash-producing, freeze-dried foods. They really aren't necessary for most backpacking or camping. Focus on compact, high-protein foods such as cheese, peanut butter, and chocolate chips. Some other foods that can be very useful for hiking include canned fish, pasta, hard-boiled eggs, rolled oats, and crackers. A small camp stove and a single pot will add some weight to your pack but will allow you a hot meal, something that will be greatly appreciated after a hard day's hike. Protein powder that can be mixed with water can be helpful when experiencing an energy crash.
Your necessities will vary widely depending on the length, location and climate of your trip. You may need clothing for various conditions: hiking boots, lightweight sneakers, shorts, long pants, hat for rain and bugs, rain gear and a wool sweater. If you are going into the wild, you will probably want a compass, topographical maps, a small mirror for signaling, and a good knife. A length of lightweight rope or cord is useful for any number of things. A couple of plastic trash bags can be stored at the bottom of your pack and pulled out to cover your pack when it rains or to stuff things into. A small first aid kit, a needle and thread, a pen and paper, and a toothbrush will also be appreciated on the trail.
