What is Newton's First Law commonly referred to as?

Newton's First Law is commonly referred to as the Law of Inertia. This fundamental principle states that an object at rest will remain at rest, and an object in motion will continue in motion with the same speed and in the same direction unless acted upon by a net external force. The concept of inertia relates to the inherent property of matter to resist changes in its state of motion. Inertia is a measure of how much an object opposes changes to its velocity; it is greater for heavier objects.

This law emphasizes the importance of understanding how forces influence the motion of objects and establishes a framework for analyzing motion in physics. It lays the groundwork for subsequent laws of motion by highlighting the concept that external forces are necessary to change the state of motion of an object.