Hello and welcome!
I would install the Synaptic package manager, you can think of it as the "pro" version of the Software Centre.
Code:
sudo apt-get install synaptic
Bear in mind that you cannot run Synaptic and the Software Centre simultaneously as they are both using the the same "apt" utility.
In Synaptic you can easily select things like "Status>Installed" which shows you what is actually installed.
If you then right click on an application, select "Properties" and open the tab "Installed files" you can find, among other things, that some documentation is installed in a place that you may not have known about.
You can copy the location then when in the Nautilus file manager press Ctrl+L to change the navigation menu and paste the location straight in.
Synaptic is very powerful so try not to remove vital system utilities.
As for the command line install Guake and you will have a cool drop down terminal to impress your friends with your hacker skills
It's also very handy. If you like it then add it to "Startup Applications"
Code:
sudo apt-get install guake
Two commands that I still have a problem with are "find" and "locate". Learn about those and maybe you can give me advice later
Code:
man find
man locate
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