Alien allows you to convert LSB, Red Hat, Stampede and Slackware Packages into Debian packages, which can be installed with dpkg. It can also generate packages of any of the other formats. This is a tool only suitable for binary packages.
Alien should not be used to replace important system packages, like sysvinit, shared libraries, or other things that are essential for the functioning of your system. Many of these packages are set up differently by Debian and Red Hat, and packages from the different distributions cannot be used interchangably. In general, if you can’t uninstall the package without breaking your system, don’t try to replace it with an alien version.
For demoinstration we downloaded an rpm package version of afio and will convert it into deb package file with this command: alien afio.rpm -d
It did generate some warning, but created the deb file, which I was able to install without any problem.