an optical disc drive is a disk drive that uses laser light or electromagnetic waves within or near the visible light spectrum as part of the process of reading or writing data to or from optical discs.
the eject button is used for eject the optical disk drive
the power botton is used to turn on and off the computer
the audio out is used to connect the speakers
the audio in is used to connect the earphones
the usb port is used to connect with an external devices.