You see the home screen when you turn on and unlock your phone or touch .
Your home screen extends beyond the initial screen. Swipe right or left to see additional pages. To add a page to your home screen, drag an app shortcut or widget to the edge of an existing page where you want another to appear and place it on the new page.
Here are the parts of your home screen:
Status bar: Displays the time and icons that tell you about your phone's battery and network connections. Swipe down to get to your settings and handy toggle switches.
Widget: You can add widgets to your home screen for quick access to information or frequent tasks.
Shortcut: Opens an app or a web page. You can add shortcuts to apps you use frequently, instead of opening and scrolling through your list of all apps.
Favorites tray: Provides one touch access to your most-used apps from any of the home screen pages. To open the list of all your apps, touch .
Navigation: takes you back one screen. returns you to the home screen from any app. lets you switch between recent apps.
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takes you back one screen. 
lets you switch between recent apps.