Alt+Tab or Ctrl+Tab
Pressing Alt+Tab switches between open programs moving forward. For example, if you have your browser window open and other programs running in the background press and hold Alt and then press the Tab key to cycle through each open program.
On Apple computers, instead of using the Alt key use the Command (Cmd) key. For example, Cmd+Tab to switch between open programs.
Press Ctrl+Tab to switch between tabs in a program. For example, if you have multiple tabs open in your Internet browser, press Ctrl+Tab to switch between them.
Adding the Shift key to Alt+Tab or Ctrl+Tab moves backward. For example, if you are pressing Alt+Tab and pass the program you want to use, press Alt+Shift+Tab to move back to that program.
Windows Vista, 7, 8, and 10 users can also press the Windows Key+Tab to switch through open programs in a full screenshot of the window.
Click here to see the next keyboard shortcut.