PSM1 is an extension that holds files that store a script module written for the shell of the Windows Power Shell operating system. It is a kind of library that can be reused for scripting. Most often it contains ready-made functions that can be called in scripts.

PSM1 are modules that allow you to use the advanced features of the Power Shell system. Scripts are files that play a similar role to BAT or CMD files and allow you to automate certain activities in the system.