Answer by ericornelissen for How to open atom using a "atom ." command in terminal?

If you're on Windows, you'll have to go to the enviroment variable select and edit the variable path copy and paste the value down the below.

C:\Users\<username>\AppData\Local\atom\bin

You can do this by opening the run dialog (win+r), type "SystemPropertiesAdvanced.exe" and hit enter. Here you should select "Environment Variables..." and edit the Path for your user (because atom is probably installed only for you).