README

Author: markhuang1212

README.md

@@ -2,6 +2,10 @@
 
 This is a backend for grading C++ code in a secure and controlled manner.
 
+## Motivation
+
+Code grading can be a difficult task, and this project aims to simplify that. No matter you want to teach people how to define a variable, how to write a function, how to write an algorithm, or how to write codes that calls other external api, `code-grader` provides a customizable framework to help you do that.
+
 ## Usage
 
 ```shell