Backup Lightroom images only

I bought a My Passport 4tb drive with the idea that I could use it to backup my Lightroom images only. Is that possible or am I out in left field. Using a iMac with Sierra. Appreciate any help. Thanks

Hello, MARNIGIRL

Well, I would like to inform you that WD’s hard drive is a plug and play mass storage device, it is capable of storing data on it, in form of 0 or 1. you can definitely use the drive to backup the Lightroom image on it but how? it depends on you which backup application are you using?
Macintosh does have Time machine application which is designed to take backup of the data on it, in order to schedule the backup with the selected files then please contact Apple support for this.