Samsung Galaxy S III User Manual page 282

2. Tap the ON/OFF slider to turn Wi-Fi on.
 Wi-Fi is enabled. You will see the names and security settings of in-range Wi-Fi networks.
To disable Wi-Fi, tap the ON/OFF slider again.
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3. Tap a Wi-Fi network, enter the password, and tap Connect.
 Your phone is connected to the selected Wi-Fi network.
Settings 273