Itunes Folder Questions

First off, I am fairly new to Mac. Having purchased a MacBook Pro about 6 months ago and a Macbook 3 months ago for my wife we are both still very much in our learning curves. After years in the PC world (we both still are for work) it is hard but very fun learning a new operating system. So, my question, I deleted a folder of music that was given to me to look through and decide if I wanted or not. I had put the music on my MacBook Pro hard drive off of an external hard drive. This music was never imported into my itunes itunes library. In doing so I also deleted a file "itunes music library.xml". What was this files function? Before finding this forum I read that if this happens go into itunes, file, import library, which I did and this file is back. Also a file library.xml came with it that is setting outside my itunes folder. Any help on this?

Thanks

he purpose of the iTunes Library.xml file is to make your music and playlists available to other applications on your computer. If you delete the file, iTunes creates a new copy from the iTunes Library file.
Your iTunes Library file may become damaged and cause iTunes to become unresponsive. The "iTunes Library.xml" file may be used to re-create a new iTunes Library file.

The moral of the story is, like iPhoto, don't go messing around within the application's Library folders. It can lead to all sorts of problems.