1. Contains the Ozone Layer: The stratosphere is home to the ozone layer, a vital region of the atmosphere that absorbs most of the Sun's harmful ultraviolet (UV) radiation. This protects life on Earth from the damaging effects of UV rays.

2. Temperature Inversion: Unlike the troposphere where temperature decreases with altitude, the stratosphere experiences a temperature inversion. This means that the temperature generally increases with altitude. This is due to the absorption of UV radiation by the ozone layer.

3. Stable and Calm: The stratosphere is generally a very stable and calm layer of the atmosphere. This is because there is very little vertical mixing due to the temperature inversion. This stability makes it an ideal layer for high-altitude aircraft travel.