A vector is a quantity with both magnitude and direction, also called a vector. Some physical quantities have only numerical values, no direction, and some are positive and negative.

1, scalar is also called "no vector". Some physical quantities have only numerical values, no direction, and some are positive and negative. The operation between these quantities follows the general algebraic law. Generally speaking, scalar is a quantity with only size and no direction.

2. A vector is a quantity with both magnitude and direction, also called a vector. Generally speaking, it is called vector in physics, such as speed, acceleration, force and so on. Putting aside practical significance, it is abstracted as a concept in mathematics-vector. In the computer, the vector diagram can be infinitely enlarged and never deformed.

3. The vector expression of physical laws has nothing to do with the choice of coordinates. Vector symbols provide a simple and clear form for expressing physical laws and simplify the derivation of these laws, so vectors are a useful tool for learning physics.