[1] MAML is a departure from all previous types of user assistance for Windows operating systems.
Previously, user assistance for Windows operating systems used Microsoft Compiled HTML Help files, which contains little machine-readable semantic information.
The most significant aspect of MAML is that it shifts the production of user assistance to the concept of structured authoring (somewhat similar to DITA or DocBook).
[2] One notable feature is guided help (active content wizard), which allows the help file to either run a task automatically or highlight the parts of the screen a user should interact with step-by-step.
The feature was a notable aspect of Project Longhorn, yet Microsoft opted not to incorporate it into the ultimate release of Vista.