What is defined as the total length of the path taken from the initial position to the final position?

The concept defined as the total length of the path taken from the initial position to the final position is known as distance. This term specifically refers to the scalar quantity that measures how much ground an object has covered during its motion, regardless of the direction taken. Distance is simply a measure of the actual path length and does not account for the starting and ending points' positions relative to each other.

In contrast, displacement is a vector quantity that measures the straight-line distance from the initial position to the final position along with the direction. Speed refers to how fast an object is moving, specifically the distance traveled in a specific time frame, without considering the direction. Acceleration measures the rate of change of velocity, indicating how quickly an object's speed changes over time. Each of these concepts is related to motion but serves a different purpose in describing it.