Start Button - Asus ASUSPRO P2520SJ E-Manual

Start button

Windows® 8.1 features the Start button which allows you to switch
between the two most recent apps that you opened. The Start button
may be accessed from the Start screen, while on Desktop mode, and on
any app that is currently open onscreen.
Start button on the Start screen
NOTE: The actual color of your Start button varies depending on the
display settings you chose for your Start screen.
Hover your mouse pointer over the left corner of your Start
screen or any opened app to call out the Start button.
Notebook PC E-Manual
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