Answer: “Tethering” or “Mobile HotSpot” allows internet-enabled mobile devices such as smart phones to be used as a modem for another device (e.g. laptops, tablets).
The connection is made wirelessly and enables users to go online with one of these other devices when internet access or public hotspots are not available.
Tethering is not free but can save you money by allowing you to take advantage of data service you are already paying for on your smart phone (i.e. 3G or 4G LTE Service), thereby eliminating the need to purchase separate data plans for your other devices.
Other benefits include more secure web surfing as opposed to public hotspots. Good for mobile personnel who primarily use one device and need the other device to have a cellular connection on an intermittent basis.