Unlike traditional mobile phones, Satellite phones use a network of satellites that orbit the earth and relay signals back to handsets on the ground.  Satellite phone kits usually come in a portable carry case, making them relatively easy to carry from location to location, although they do tend to be generally larger than as standard mobile phone.  You will probably see Satellite phone handsets used on military documentaries on television both on land and at sea.  It is absolutely imperative that communication is established with troops or workers in remote locations as it can help evade potential crisis and in many situations save lives.  Through the use of satellite tracking and communications it can now help to save many lives and prevent unnecessary loss.