Is the My Book a true mirror? or does it keep all your files, even deleted ones?

Hi,

I recently got the My Book Essential because mozy got too expensive and carbonite is going to take more than half a year to back up my files.  I read the online pdf manual, but I still am a little unclear on how the My Book smartware actually works. 

Once you make your initial back-up, does the software continuously keep an exact copy of the drive you selected?  I know you can set it to make multiple copies of files so you have previous versions – but what if you delete a file?  Does the file disappear on the My Book?  It would seem like if it kept every new file you made and then deleted, you could fill it up with junk fairly quickly.  But at the same time, I would like a copy to be on the My Book just in case I decide I shouldn’t have deleted the file in the first place. 

Smartware doesn’t backup the entire drive only certain file types. I only used it once last year and uninstalled I didn’t like it. They have made some changes but I’m really not that familiar with it.

Joe

Check this link below:

http://wdc.custhelp.com/app/answers/detail/a_id/3644/session/L3RpbWUvMTMyMjgzNDQyNy9zaWQvb3RRX3FBS2s%3D