Hiking equipment
According to Tom Brown, the basic plan for survival is in the order of shelter (including clothing), water, fire, and food. Cody Lundin writes about the "Rule of 3s"; this relates to human survival without basics: three minutes without air, three hours without shelter, three days without water, or three weeks without food.
Space Saves Society
Water covers the largest percentage of our planet’s surface and it is vital for our survival. However, many areas still suffer from absence of drinking water. The Water Supply and Sanitation Collaborative Council (WSSCC) refers that “Today 2.5 billion people, including almost one billion children, live without even basic sanitation. Every 20 seconds, a child dies as a result of poor sanitation. That's 1.5 million preventable deaths each year.”