
What difference between error, warning and message?

Permission denied:
Just delete and restart rstudio for windows.
C++ error:
Install Rtools for windows.
Permission denied:
Just delete and restart rstudio for windows.
C++ error:
Install Rtools for windows.
No notes.
Project: A folder with a .Rproj file in it.

Script: A .R file.

Setting CRAN mirror in China.
Tools -> Global Options -> Packages ->Management
Best CRAN: Hefei > Lanzhou > Beijing
A temporary solution:
options("repos" = c(CRAN="https://mirrors.ustc.edu.cn/CRAN/"))
What difference between error, warning and message?

Permission denied:
Just delete and restart rstudio for windows.
C++ error:
Install Rtools for windows.
Using Linux Desktop Distribution
Ubuntu Desktop 18.04 and 20.04.
GithubDesktop for git.
VS code for anything.
Typora and Notepad-- for markdown.