Windows system environment variables
When writing batch processing, directories such as C:\ProgramData and C:\Users\Home\AppData\Local are often used. Sometimes the user names are different. In this case, we need to use variables. Variable comparison table Reference reading: https://www.askvg.com/list-of-environment-variables-in-windows-xp-vista-and-7/ https://windowsloop.com/list-of-all-environment-variables-in-windows-10/ https://ss64.com/nt/syntax-variables.html