How does WD security encryption work?

I was going to turn on the password encryption on my harddrive but im worried and unsure of exactly it works?

When i turn on the password is all my data on the harddrive instantly encrypted and protected? does it take several hours to encrypt all the data?

What if I want to turn off the password and decrypt my harddrive? does that create any problems or take hours to decrypt everything?

When encryption is active, your hard drive will not be detected/mounted/accessible until you input your password. Encryption and decryption for data management into or from the hard drive is managed on the fly with little to no loss in performance.

If you disable your password your hard drive will simply mount without asking for credentials (Like a regular hard drive). You do not need to run a separate process to decrypt your data.

thanks, so If i understand this properly this software just puts an encrypted password lock on the harddrive instead of encrypting any of the files inside the harddrive?

It seems different on computers because you have the option to encrypt the entire harddrive but that takes hours and hours as software goes through each file and encrypts them all individually