Hi Andre,
Thanks for reverting. Earlier any command starting with "~" was not working for me either in RStudio or using Gitbash. I have unchecked and rechecked the "attributes" box in the "properties" for "documents" folder which is an intermediary between the "user (my name)" and my RStudio project directory (folder). After doing so, "~" command is working in both RStudio and Gitbash. However, my home directory is showing as my user directory (username@computerrname). Besides, at the end of each command line after I execute "cd" command, I get the string "(master)" for sub directories below "documents" folder. I am not sure what does this "master" string mean....