multiple preinstalled programs with similar jobs

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http://askubuntu.com – I have unity, gnome-shell and xubuntu on my laptop. They all have their favorite preinstalled programs it seems. Do I really need three text editors for example? Could I remove two and just have the other desktops use the one I keep? It seems as though I could get rid of all video playback programs as well and just use vlc for example. Am I going to mess something up? I am new to all this. (HowTos)