I've noticed that when I uninstall a program, it usually doesn't free up as much memory as it occupied when originally installed. This makes me think that the uninstall process is not as clean and complete as it should be.

Today, while adding a book to my FBReader library, I saw the following in my /home/user directory:

Edit: tried to post a screenshot with a Picasa link, but it didn't show up. Not sure what's wrong. I'll try to explain with words.

In the /home/user directory, I noticed hidden folders for programs I had uninstalled through the Application Manager months ago, including a .boswars folder. It looks to me as though these applications are leaving some trace of themselves behind.

My question is this: how can I access and delete those hidden files? So far FBReader is the only program I've been able to see them in.

Also, I'm new to Linux and have zero experience with Terminal, so if your solution involves using terminal, please talk to me like I'm 5.

Thank you.

If, like me, you don't know Linux, I'd be hesitant to delete those files. But you can find, and delete, them with the emelfm2 file manager. The H icon shows and hides hidden files and folders. Hidden files start with a period.

This is a feature not a bug: this way, when you decide to install again that particular application, you'll find it already configured the way it was.
There are ways to uninstall both the application and its configuration; they need the use of command line and superuser mode - apt-get purge is the command.

I've been looking into this as well and found the purge command earlier. However when I run "apt-get purge" as root I get

"E: Invalid Operation purge"

Am I doing something wrong with the command?

Shouldn't it be