For Day Hikers

• Water
• Food
• Map, plus compass or GPS for longer trips
• Rain gear
• Hat
• First aid kit with bandages, antibiotic cream, and items you need for your personal health and safety
• Insect repellent
• Sunscreen
• Sunglasses
• Small flashlight
• Optional personal items such as a camera, sketch pad, or field guide
  

For Backpackers

All of the elements needed for a day hike, plus:

• Water filtration method
• Adequate food for the length of the trip
• Camp stove and fuel
• Cook pot and fork or spoon
• Tent, hammock, or bivy
• Sleeping bag and pad
• Headlamp or other light source with spare batteries
• Duct tape for emergency repairs
• Bandana
• Biodegradable soap or alcohol-based hand cleaner
• Spare set of dry clothes, especially socks