This is a list of common terms and abbreviations used in the satellite community.
In the context of spaceflight, a satellite is an artificial object which has been intentionally placed into orbit. Such objects are sometimes called artificial satellites to distinguish them from natural satellites such as Earth's Moon.
The azimuth is the angle between the north vector and the perpendicular projection of the satellite (or star) down onto the horizon. Azimuth is usually measured in degrees (°). The concept is used in navigation, astronomy, engineering, mapping, mining and artillery.
Sometimes referred to as elevation, is the angle between the object and the observer's local horizon. For visible objects it is an angle between 0 degrees to 90 degrees.
Horizontal coordinate system
Sometimes also called the az/el system, the Alt/Az system or the altazimuth system (from the name of the altazimuth mount for telescopes, whose two axes follow altitude and azimuth) is a celestial coordinate system that uses the observer's local horizon as the fundamental plane. It is expressed in terms of altitude (or elevation) angle and azimuth.