Check out example codes for "set path in windows". It will help you in understanding the concepts better.

Code Example 1

set path=C:\Program Files\Java\jdk1.6.0_23\bin

Code Example 2

FOR MAC:

 1º - Open Finder
 2º - Choose Go > Go to folder
 3º - Go to ~/Library/
 4º - Look for hidden files: Cmd + Shift + . (dot) 
 5º - Depending on the shell you use, the file can be .bash_profile, or .bashrc, or .zshrc, ...
 6º - Open that file in the text editor
 7º - Add the new path like: export PATH="$PATH:"User/new_path/..."
 8º - Test in your command line if it worked: echo $PATH

Code Example 3

#update path only for the current session
set PATH=%PATH%;C:\your\path\here\

#update the path permanently
setx /M PATH "%PATH%;C:\your\path\here\"

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