Yes, for the PS3/PS4 you can use a USB thumb/external drive to back up your ps3/4 saves as long it is not copyright prohibited. You need PS+ to save the copyright files though.
Free Step Dodge
lotr9690
You can also use certain external drives but USBs are preferred.
Nameless Sama
Thank you both I have 2 questions. Do you lose your back up save file when your psn+ membership expire ? 2 question is do you know if it is possiable to import save data from someonelse to your account ?