How do you transfer an Itunes library from an external hard-drive to a Mac?

My Itunes library was transferred onto an external hard-drive. How do I access my Itunes library after I plug it in to my new computer? Please include step-by-step instructions.How do you transfer an Itunes library from an external hard-drive to a Mac?
Is "library" the database file named "iTunes Library" or is it your music folder?

For the actual library (the database file), copy it to:
yourhomefolder /Music /iTunes
If you have already used iTunes on this Mac, you already have an iTunes Library file there, so either (1) replace the old iTunes Library file with the new one (what you want for a new system), or
(2) use two different iTunes libraries (not what most people want) like this:
-- If iTunes is open, quit it.
-- Make a folder called "iTunes 2" or whatever name you choose at whatever location you wish.
-- Put the iTunes Library file there.
-- Make a folder inside "iTunes 2" called "iTunes Music"
-- Put the music files for this new library here.
-- Hold down the Option key while you open iTunes.
-- In the dialog that appears, do one of the following:
-- To create a new library, click Create Library.
-- To choose a different library, click Choose Library.
-- Then navigate to "iTunes 2".

For the folder of music files, you simply drag it from the external HDD to the place you want it to be. I keep my "iTunes Music" folder on the Windows partition, using the free NTFS-3G driver to enable the OS X system to add new songs. If you want to put the music files at the default location, that will be....
yourhomefolder/Music /iTunes /iTunes Music

If you want to keep the two iTunes Library files separate (with separate music folders), that's described above. If you want to combine everything...
-- Quit iTunes.
-- Trash the "iTunes Library" file.
-- Go to:
yourhomefolder /Library/Preferences
-- Trash the file "com.apple.itunes.plist"
-- Launch iTunes. Agree, yes or no about Internet (your choice), When it asks if you want to "Find music files", choose "No, I'll add them myself later". {If you let it chose by itself, it will find not only your music files, but also lots of sound files that are not what you want to add.}
-- Go to File %26gt; Add to library. Navigate to yourhomefolder /iTunes /iTunes Music.
-- Click to add.
-- Take a long break.How do you transfer an Itunes library from an external hard-drive to a Mac?
See Apple's article, linked below, "How to move your Music to a new computer"How do you transfer an Itunes library from an external hard-drive to a Mac?
Oh my....big troubles