The Ten Essentials are survival items that hiking and Scouting organizations recommend for safe travel in the backcountry.
The Ten Essentials first appeared in print in the third edition of Mountaineering Freedom of the Hills Mountaineers (January 1974). Many regional organizations and authors recommend that hikers, backpackers, and climbers rigorously ensure they have the ten essentials with them. However, personal preferences and differences in conditions may dictate otherwise and with experience most adventurers add and subtract from the list depending on the situation. Some lightweight hikers do not always carry all of the items and believe it is an acceptable risk they take in order to travel light and fast.
According to the eighth edition of Mountaineering: The Freedom of the Hills book there are ten essentials, which are now referred to as the "classic" essentials. While still valid and widely used they do not reflect modern outdoor sports and all of the new gadgets that now are common.
In 2003, the essential list was revised as part of the seventh edition of Mountaineering: The Freedom of the Hills to keep up with modern equipment. The current edition, 8th edition continues with the new essentials list with no major revisions. The new list takes a "systems" or functional approach.
The textbook recommends supplementing the ten essentials with:
Some experts recommend having duplicates of the Essentials in different sized kits: in pockets, on key rings, in pocket kits, belt pouches, belt packs, day packs, and backpacks.
Other outdoor organizations have variations of the Ten Essentials pertinent to local conditions.
Boy Scouts of America's "Scout Basic Essentials" are quite similar (Map and Compass, Sun Protection, Extra Clothing, Flashlight, First-Aid Kit, Matches and Fire-starters, Pocketknife, Trail Food, Water Bottle, and Rain Gear.)
Utah's Wasatch Mountain Club lists extra water in place of food, as Utah is mostly desert terrain, and water is more difficult to find.