Wi-Fi
Drag the Wi-Fi switch 
to the right to turn on Wi-Fi functionality to connect to available Wi-Fi networks. Drag it to the left to turn it off.
Wi-Fi settings
Turn Wi-Fi on, then tap Wi-Fi to access the following settings:
Notify Me: Checkmark to be notified when a Wi-Fi network is in range when you launch an application.
Optimize Wi-Fi usage: Opens a dialog box to optimize Wi-Fi usage when launching applications or uploading/downloading large files.
WI-FI NETWORKS
The list of all of the Wi-Fi networks that are within access range. Tap one to access it.
Tap SEARCH at the bottom of the screen to scan for available Wi-Fi networks. Tap ADD NETWORK at the bottom of the screen to add a new network.
For the following additional settings, tap the Menu Key 
> Advanced.
Keep Wi-Fi on during sleep: Allows you to set Wi-Fi during sleep.
Avoid poor connections: Checkmark to only use a Wi-Fi network that it has a good Internet connection.
MAC address: Displays the MAC address.
IP address: Displays the IP address.
Manage networks: Allows you to specify the order in which the available networks will be detected.