Software update programs – which to keep and which to remove?
$ dpkg -l | grep softwar
ii brltty 6.4-4ubuntu3 amd64 Access software for a blind person using a braille display
ii docbook-xml 4.5-11 all standard XML documentation system for software and systems
ii espeak-ng-data:amd64 1.50+dfsg-10 amd64 Multi-lingual software speech synthesizer: speech data files
ii gnome-software 41.5-2ubuntu2 amd64 Software Center for GNOME
ii gnome-software-common 41.5-2ubuntu2 all Software Center for GNOME (common files)
ii gnome-software-plugin-flatpak 41.5-2ubuntu2 amd64 Flatpak support for GNOME Software
ii gnome-software-plugin-snap 41.5-2ubuntu2 amd64 Snap support for GNOME Software
ii libdv4:amd64 1.0.0-14build1 amd64 software library for DV format digital video (runtime lib)
ii libespeak-ng1:amd64 1.50+dfsg-10 amd64 Multi-lingual software speech synthesizer: shared library
ii libfluidsynth-dev:amd64 2.2.5-1 amd64 Real-time MIDI software synthesizer (development files)
ii libfluidsynth3:amd64 2.2.5-1 amd64 Real-time MIDI software synthesizer (runtime library)
ii libqpdf28:amd64 10.6.3-1 amd64 runtime library for PDF transformation/inspection software
ii libwildmidi2:amd64 0.4.3-1 amd64 software MIDI player library
ii python3-software-properties 0.99.22.7 all manage the repositories that you install software from
ii software-properties-common 0.99.22.7 all manage the repositories that you install software from (common)
ii software-properties-gtk 0.99.22.7 all manage the repositories that you install software from (gtk)
ii steam:i386 1:1.0.0.74-1ubuntu2 i386 Valve's Steam digital software delivery system
ii xbrlapi 6.4-4ubuntu3 amd64 Access software for a blind person using a braille display - xbrlapi
The above shows a Ubuntu 22.04 system having two types of software update files. Namely, :
gnome-software,gnome-software-common,gnome-software-plugin-flatpak,gnome-software-plugin-snappython3-software-properties,software-properties-commonandsoftware-properties-gtk
On the dock, these two app icons are present(see below). Both programs do the same job.
Am I correct to think that only one of them is needed? Which should I uninstall to avoid duplicated programs residing in the system?
The orange icon is the "Snap store". That is the default Ubuntu software center. It is based on the Gnome Software center, but is installed as a snap package. Thus, it does not appear in the output of dpkg -l, but will appear in the output of snap list as snap-store.
The gray icon is the Gnome Software center. It appears in your list as the gnome-software packages. It is not by default installed on an Ubuntu 22.04. If it is present on your system, then that is because either you installed it, or you upgraded on top of an install of an older release.
Am I correct to think that only one of them is needed?
Yes, you are correct.
Which should I uninstall to avoid duplicated programs residing in the system?
gnome-software if you want to use the software store that by defauls comes with Ubuntu. Use sudo apt autoremove gnome-software to remove it and all its dependencies that are not needed for other software.