schtasks.exe is the Task Scheduler Configuration Tool and is used to schedule tasks so that they run automatically. It replaces the deprecated at.exe command line interface.
schtasks does not have all options that the Task Scheduler in control panel (under Adminsitrative Tools) provides. For example, it does not allow to influence power (battery) related settings (see this Stackoverflow answer).
schtasks /create /sc minute /mo 2 /tn "TestTask" /tr "%cd%\the-task-to-be-scheduled.bat %cd%"
@rem use (possibly as administrator)
@rem schtasks /Delete /TN TestTask
@rem to delete the task again
@rem
@rem See also
@rem --------
@rem run -> taskschd.msc
@rem
@rem https://renenyffenegger.ch/notes/development/tools/scripts/personal/notify_me_at_bat
notify_me_at.bat and notif.ps1 are two commandline scripts that use the scheduler to pop up a message box at a given time in order to notify the user of something.