What is called the axis of rotation of a rigid body?

The axis of rotation is called a relatively stationary straight line around which a rigid body rotates. In this case, a necessary condition is that at least 2 points of the body must be motionless. Interestingly, the axis of rotation may not pass through the body, but be located outside of it. The axis may or may not be movable. A good visual example is the rotation of our planet around its axis, and in a reduced form this is illustrated by the globe.

One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.