When you double click on a deb package in Ubuntu 23.10 an error appears to tell you "there is no app installed for 'Debian package' files". In this post I
It can install a service that will start automatically after install, so for all intents and purposes, if you click it and enter your sudo password, you might as well have run an executable.
A deb is not an executable. You can’t run it
And neither is a doc file, but most OSes would open up a compatible word processor.
It has pre and post-install scripts. Once you hand it off to dpkg, it can do pretty much anything.
It can install a service that will start automatically after install, so for all intents and purposes, if you click it and enter your sudo password, you might as well have run an executable.