Steroids and other medications. Long-term use of oral or injected corticosteroid medications, such as prednisone and cortisone, interferes with the bone-rebuilding process. Osteoporosis has also been associated with medications used to combat or prevent: Seizures; Gastric reflux; Cancer; Transplant rejection; Medical conditions
The main functions of using a compass are: 1  tell which direction you are traveling - your heading. 2  tell which direction an object is from you - its bearing. 3  keep you following a straight line of travel. 4  orient a map - aligning a map with the actual land.  triangulation - determining your location with a map.
A compass is a navigational instrument that shows directions. The compass was invented by Chinese between the 2nd century BC and 1st century AD. It was first used in Feng Shui, the layout of buildings. By 1000 AD, navigational compasses were commonly used on Chinese ships, enabling them to navigate.