Onkyo HT-SP908 7.1-Channel Home Theater with iPod Dock

Power per channel (RMS): This refers to the amount of power (watts) the source unit sends to the right and left front channels, as opposed to power sent to other speakers.

THD @ rated power: THD stands for total harmonic distortion and is rated as a percent of the total musical signal.

S-video inputs: This round connector carries video only, no audio, and while it will give you better picture quality than a Composite connection it is still limited to 480i resolution and cannot pass high-definition.

Number of component video inputs: These inputs use three RCA cables to carry a video signal. Receivers and sources with these inputs will be able to route video signals from more than one high-resolution source to a TV with component inputs.

HDMI inputs: The number of HDMI inputs a TV has. The more inputs, the more components can be added to the system.

Number of digital coaxial inputs: A single coaxial cable can transfer a multi-channel signal from a digital source, like a DVD player, to a receiver, where it will be processed and turned into surround sound. The more inputs you have, the more components you can hook up.

Stereo audio inputs: A set of RCA audio outputs that let you connect a TV to an audio system. This type of connection will only give you stereo, though many audio systems can turn into surround modes like Dolby Digital Pro Logic II for a more enveloping experience.

Disc capacity: The number of discs a CD player can hold and play.