Yes, the Mac has several shortcuts like Ctrl-Alt-Del, because what Ctrl-Alt-Del does has changed in different versions of Windows. Which behavior of Ctrl-Alt-Del were you looking for? You can press Command-Option-Esc to bring up the Force Quit Applications dialog box. This is very similar to the Task Manager you get in older versions of Windows if you press Ctrl-Alt-Del, in that you get a list of apps you can terminate even if an application has locked up. In Windows 8, Ctrl-Alt-Del brings up a screen that says Lock/Switch User/Sign Out/Change a Password/Task Manager. I guess something similar on the Mac is if you hold down the Power button on a Mac laptop to bring up the Restart/Sleep/Cancel/Shut Down dialog. Free audio visual effects software. Or you could just click the Apple menu to get most of the options in the Windows 8 Ctrl-Alt-Del screen.

Or if you want to force restart the computer, press Command-Control-Power. But since this is not an orderly shutdown, it is not recommended except in emergencies where no normal procedure will turn off the computer. The key is to know what the real problem is. If none of the ways to switch to other applications is working (Command-Tab application switcher, Expose, Dock.), and the Force Quit window won't come up, holding down the power button is reasonable. But if you can manage to get out of the locked up application, you don't have to force the system to shut down, just force the application to quit and then shut down or restart normally.

Note that holding down the power button for a few seconds should display that shutdown dialog, but if the system is really screwed up that dialog may not appear. In that case, keep holding down the power button, because as with most Windows PCs, when you keep the power button held down long enough (even after whatever dialog appears or doesn't appear) the Mac will just force shutdown. Apple Footer • This site contains user submitted content, comments and opinions and is for informational purposes only. Apple may provide or recommend responses as a possible solution based on the information provided; every potential issue may involve several factors not detailed in the conversations captured in an electronic forum and Apple can therefore provide no guarantee as to the efficacy of any proposed solutions on the community forums. Apple disclaims any and all liability for the acts, omissions and conduct of any third parties in connection with or related to your use of the site. All postings and use of the content on this site are subject to the.

A control group in a scientific experiment is a group separated from the rest of the experiment, where the independent variable being tested cannot influence the results. This isolates the independent variable 's effects on the experiment and can help rule out alternative explanations of the experimental results. Control is the term used to describe an object in a window or dialog box. Examples of controls include push-buttons, scroll bars, radio buttons, and pull-down menus. It may also be used to specifically describe an OLE or ActiveX object.