C Type Qualifier
[Programming Modifier](https://texonom.com/programming-modifier-cc2ff5daabd64cf4b20c93aa8011419b) 


**`const`**, **`restrict`**, **`volatile`**


### Const
Protect argument from using [Call by Reference](https://texonom.com/call-by-reference-cd8a9f46cce34bd780a32c444ea56a34) and make them read-only 
- can be in function definition header parameter declaration
- can mark a member function as const
### **const function**
Use keyword const after function declaration and heading for const function



> [형식 한정자](https://learn.microsoft.com/ko-kr/cpp/c-language/type-qualifiers?view=msvc-170)





