How do you understand "linear algebra"? _ Linear algebra

What is the practical significance of linear algebra? What is the matrix? What does the operation between matrices represent? Many people still don't understand these questions at school, so I think we should start with understanding the nature of the course.

There are only a few articles or answers that provide an understanding of the nature of linear algebra. Bloggers repeatedly read several times to deepen the understanding of the matrix in ordinary learning.

This article is for learning reference only, if there is infringement or doubt, please contact the blogger.

The nature of linear algebra
Https://www.52ml.net/13425.html

How to understand the adjoint matrix in algebra.
https://www.zhihu.com/question/39334410

singular matrices
Http://open.163.com/movie/2011/6/S/P/M82ICR1D9_M83C92ISP.html

How to understand the "rank" of the matrix.
https://www.zhihu.com/question/21605094