• Win16 applications were originally designed to run with Windows 3.x.
• The 16-bit Windows applications cannot directly transfer information to the 32-bit Windows 7 operating system. All requests for service from the Win16 environment are translated to 32-bit re- quests and vice-versa. This specif c translation situation is referred to as thunking.

Read more about thunking at:
http://msdn.microsoft.com/en-us/library/ff565689(VS.85).aspx.
• All Win16 applications run in a single VDM by default because this is the expected behavior in a Windows 3.x environment. Note that since all Win16 applications run in the same vir- tual process by default, any one application that crashes can crash all other Win16 applications running with it in the VDM. It is possible to run a Win16 application in its own Win16 VDM, but this is not the default behavior and results in slower performance overall due to increased overhead.
• A Win16 environment can take a lot of time to initialize the f rst time it is started. For this rea- son, once a Win16 VDM is created it is not immediately shut down when all Win16 applications terminate. Windows 7 f rst checks to see if any other Win16 VDMs are running. If they are, then this Win16 VDM are shut down. If there are no other Win16 VDMs, this particular one will remain running until the user logs out or shuts down the computer.

Activity 11-3