Always on USB: on even when laptop is in sleep mode.
Lock hole: Cau be used with a laptop lock to secure your laptop.

Wireless switch: Switch the wireless on/off.
eSATA: Connect to SATA devices externally.
Headphone jack: Listen to music with your headphone.

VGA: Standard video port for most monitors.
Ethernet: Connects to your network with an ethernet cable.
USB: For connecting USB devices.
Display Port: New port for connecting to monitors. Becoming popular on most new monitors.

DC Jack: Power connector where AC adapter plugs into.