Altitude and Azimuth are coordinates used to describe the position of a celestial object in the sky at a specific time. This is called the Horizontal Coordinate System.
Altitude refers to the vertical angle between the object in the sky and the observer's horizon. This is measured in degrees. Its maximum is 90 degrees
Azimuth refers to the horizontal angle between the object in the sky and true North. This is measured in degrees and it increases due East.