Hi,
Full Disk Encryption will encrypt the computer hard drive - entirely or the partitions you define (files, folder, etc).
This means if you don't have access, you lost the password or the computer is stold, access the encripted drive won't be possible.
By encripting files and folder, I probably mean Removable Storage, a funcionality to encrypt extenal drives, such USB or SD cards. With this product, you can also allowed user to encrypt files on demand if they are using the removable storage outside of the company (agentless computer).
Hope this helps,
Regards
LG