Rob Sobers from Varonis provides a great summary on the differences between SMB and CIFS
This day and age, you should always use the acronym SMB.
I know what you’re thinking – “but if they’re essentially the same thing, why should I always use SMB?”
1.) The CIFS implementation of SMB is rarely used these days. Under the covers, most modern storage systems no longer use CIFS, they use SMB 2 or SMB 3. In the Windows world, SMB 2 has been the standard as of Windows Vista (2006) and SMB 3 is part of Windows 8 and Windows Server 2012.
2.) CIFS has a negative connotation amongst pedants. SMB 2 and SMB 3 are massive upgrades over the CIFS dialect, and storage architects who are near and dear to file sharing protocols don’t appreciate the misnomer. It’s kind of like calling an executive assistant a secretary.