Although Ubuntu comes with excellent packages that help you alter the default settings and customize the distro for yourself, tweaking a few settings however requires you to go deeper into the system.
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Plus if you do something wrong, youre probably going to end up making a mess of your Ubuntu installation. Thats where a program called Ubuntu Tweak comes in handy. Ubuntu Tweak is a little GUI based tool and it lets you edit some hidden settings on your Ubuntu installation very easily. Its similar to Tweak UI for Windows XP