HDMI - High Definition Multimedia Interface.
The connection used by many appliances for the transfer of picture, sound and control.
A.R.C - Audio Return Channel.
One HDMI socket has the ability to sent sound OUT to a soundbar / home theatre system.
M.H.L - Mobile High definition Link.
Mobile phones and tablets with the right connection can feed the picture and sound of the device to the TV.
Optical Connection - A Digital connection using light along a glass fiber length to output sound from one device to go in to another. I:E, From TV to a Soundbar.
Also known as TOSLINK or SPDIF.
R.M.S - Root Mean Square, Or in simpler terms, The power output of an Amplifier before sound distortion becomes more obvious.
Always look at R.M.S in favour of 'MAX' or 'P.M.P.O'
Bluetooth - A wireless connection beween two devices to transmit Audio and other data. Typically from a Mobile Phone to a Hi-Fi system.
Internet Radio - With a compatible device and an Internet connection you can listen to Radio stations from around the world. An almost unlimited choice of music and pretty much guaranteed reception as long as you have reliable Internet.
N.F.C - Near Field Communication, Used in many walks of life but used to connect or 'pair' two compatible Bluetooth devices very easily by 'touching' together at the relevant points.
D.A.B / D.A.B+ - Digital Audio Broadcast, or Digital Radio allows for a clearer sound and more station choice, Many areas can receive D.A.B but coverage is improving all the time.
The UK started using DAB with parts of Europe using the DAB+ band, The main difference is more station choice and an improved 'codec' which can result in better sound in lower signal areas.
Currently the UK has no plans to fully move to DAB+.
Media Streaming - Usually a feature of an Internet Radio, Allows you to play music over your local network, From a Computer, Mobile phone or Tablet.
Sometimes with the aid of an App or Software, Can allow multi room control.
Coaxial Digital Connection - Uses a single Phono lead to transfer Audio, Much less common than Optical.
Auxiliary input - An Analogue Audio connection, Usually as a 3.5mm connection on the front but can be a pair of Phono sockets on the back of an appliance.