Restart with the same windows and programs open I have an iMac iOS 10.11.4. When I restarted it, all the programs and windows came back as it was. I do not why, it does not happen anymore. How can I have that feature back?
This is a feature introduced back with Lion, and it is called Resume. 
When you are restarting you mac there is a popup menu, that is asking you if you want to reopen windows when logging back.
If you check this box, all the programs and windows should come back as it was.