Directories are an important though rarely mastered component of enterprise application development. For the Windows® platform, Microsoft provides three primary directory platforms: Active Directory® Domain Services, the local Security Account Manager (SAM) data store on every Windows computer, and the relatively new Active Directory Lightweight Directory Services or AD LDS (which you may have previously known as Active Directory Application Mode or simply ADAM). While most enterprise developers know at least the basics of SQL programming, far fewer have experience programming directory services.Do I understand correctly that if I am mainly concerned with the Active Directory, I need to ignore the Security Account Manager (SAM)? Since, in my understanding, the SAM is something in every Windows computer.