This usually occurs when git is not an available command from the command prompt. To add git to your path:

Windows
1. Right click "Computer" -> "Properties"
2. "Advanced system settings" in the left side column -> "Environment Variables" button.
3. Find the "Path" variable in the System variables box, click it, and then click the Edit button.
4. Add ;\cmd;\bin to the end of the Path variable string.
For example, my is ;C:\Program Files (x86)\Git so I would add ;C:\Program Files (x86)\Git\cmd;C:\Program Files (x86)\Git\bin to my path as below.

Mac OS
1. run the command add the line to your ~/.bash_profile file export PATH=$PATH:/bin
2. Once that is added to your .bash_profile, run the command source ~/.bash_profile to add the git bin folder to the PATH for this terminal window/tab and any future terminal windows.

> Once you have done either of these methods, open a cmd/terminal window and type git to see if it is a recognized command.