How to automatically hide program?

[MilesAhead]

What programming language is it written in?

 

[Alejandro85]

Programs never display anything unless specifically written to do so. Check your code and try to conditoin/remove the part when it opens its UI.

If by "beep" you mean a sound, just playing audio doesn't require an user interface at all, it can be totally invisible. Even if it displays a popup of some sort, it neither requires the thing to be open for long, or even appear in taskbar.