Sony/Philips Digital Interface. Provides digital output and the best signal quality.
Connects to an external Home Theater audio system.
An SPDIF port is digital audio port. It provides stereo or compressed surround audio by way of coaxial or optical communication.
Digital audio stream
spdif is a digital audio Output, Certain a/v receivers may offer this type of connection, however if your using HDMI for audio, then their probably wont be much benefit. an RS232 port is generaly used either for software updates and servicing, or for external control of the unit via a 3rd party control system.
SPDIF is a type of digital audio connection. If you hook that up to a port on the AV receiver make sure it is marked "digital/coax", PCM etc....the connection will be orange in color, just like the output on the cable box. Now make sure your AV receiver is told what type of audio to look for on that particular input and make sure your cable box is told what type of audio to put out, not always necessary but would be in the set-up menu if needed.
An S-Video Port.
A 2-channel digital audio signal, or a encoded DTS or Dolby Digital surround sound audio stream.
S-video is better than the composite video when output to a television
An S-Video Port
Composite video out has better performance than S-Video.
A VGA or DVI port provides video only display.
The mini DVI to VGA cord is a converter cable or adapter cable. These types of cables will take input from one type of port and convert it into output which will be sent into the second type of port. In this case it will plug in something with a mini DVI plug into a VGA port.
usually sensor or digitized voltages on the inputs. if the port is parallel port, the input doesn't have to be serialized first. Output ports usually converted back to analog for some control application via D/A converters