After buying your Android phone the first thing you should learn is to connect it to your pc computer or mac via the USB cable that comes with the mobile phone. The reason for connecting it is to either charge the phone via usb or to share data, sync contact or access the internet.
Plug-in one end of the usb cable to the phone end and insert the usb 2.0 jack into your PC computer or mac. As soon as you connect your android phone to your computer via USB cable, the Connect to PC screen appears where you have to choose one of the type of USB connection available. Select one of the choices as per your need, and then tap Done to proceed.
Disk Drive Mode : If you have your microSD card inserted in your android phone then this option will come to use your android phone like storage device. Select the disk drive mode if you want to copy and share data, files, music, videos, mp3 between the microSD card and your computer.
Note : When your phone is connected to pc computer in the Disk Drive mode, you won’t be able to run applications that use that storage microSD card, such Music, Gallery etc.
Charge Only : If you only want to charge the battery while your android phone is connected to your pc computer, then select this option. The phone will remain inactive mode while charging which means you’ll be able to receive calls, messages etc.
Mobile Network Sharing: Don’t have Internet connection on your computer. Connect your android mobile and select this mode to share your phone’s mobile modem router and access the internet through the device on your pc.
If you need to change the mode of USB connection, you can do so on-the-fly, without disconnecting and reconnecting your mobile usb. Just slide down the Notifications panel, and then click notification that mentions "Select to change USB connection type" to access the "Connect to PC" options once again.
You can also choose among showing or hiding the Connect to PC screen or the default connection type by pressing Menu from Home screen, and going thru Settings > Connect to PC.
Hope this helps…