The keyboard key combination in Windows that brings an application to the foreground in lieu of using a mouse. Pressing Alt-Tab switches between all open applications in the Taskbar.
The Alt key is held down while the Tab key is pressed to cycle through the icons of all the windows. When the Tab key is released, the highlighted window is brought to the foreground.
The Mac Uses Command-Tab
In the Mac, Command-Tab is pressed in a similar manner; however, Command-Tab cycles between applications, not between multiple windows open within the application. To cycle between multiple windows within the application using the keyboard, Command-Tilde is used. See tilde