Hiking is an outdoor activity which consists of walking in natural environments, often in mountainous or other scenic terrain. People often hike on hiking trails. It is such a popular activity that there are numerous hiking organizations worldwide. The health benefits of different types of hiking have been confirmed in studies. Some of the health benefits of hiking include, but are not limited to, losing excess weight, decreasing hypertension, and improving mental health. The word hiking is understood in all English-speaking countries, but there are differences in usage.
In the United States and United Kingdom, hiking refers to walking outdoors on a trail for recreational purposes. A day hike refers to a hike that can be completed in a single day - not requiring an overnight camp. Multi-day hikes with camping is referred to as backpacking. In the United Kingdom hiking is usually called rambling, which resulted in the hiking organization named Ramblers. Bushwhacking specifically refers to difficult walking through dense forest, undergrowth, or bushes, where forward progress requires pushing vegetation aside. In extreme cases of bushwhacking where the vegetation is so dense that human passage is impeded, a machete is used to clear a pathway. Australians use the term bushwalking for both on- and off-trail hiking. New Zealanders use tramping (particularly for overnight and longer trips), walking or bushwalking. Multi-day hiking in the mountainous regions of India, Pakistan, Nepal, North America, South America, Iran and in the highlands of East Africa is also called trekking. Hiking a long-distance trail from end-to-end is also referred to as trekking and as thru-hiking in some places.  Examples of long-distance trails include the Appalachian Trail (AT) and Long Trail (LT).