Common AV Connectors Explained

This is gonna be a half-rant / half-tutorial post.

Look behind your modern tv and you will see a plethora of connections, some familiar and others that will make you say "wtf???!!!111oneoneone!!". I'm going to try simplify this for you, by ranking them in order of display quality, lobbing a picture for reference and an explanation of when they would be commonly used.

So, bingo, let's start

Worst to best ranking, with some ties.

1) RF - you should be familiar with this one already, RF=Radio Frequency,, and it is what you plug your aerial into. In the states this would be an f-connector with a screw thread, most of the rest of the world uses a push fit connector , with the socket having a female receptacle. As it says, this is for radio frequency, and will not give the best picture quality, at all. Ever. Stay Away From This if you have others options.
It looks like this


2) Composite - (NOTE: DONT CONFUSE WITH COMPONENT) composte is normally coloured yellow, the jack and the socket is yellow, it is a two wire system, one being signal and the other is a ground/shield wire. This is so common on most equipment that if you havent seen one yet you probably own a guide dog. It is better than RF, but not by much. All info has to get modulated into a single wire, and this causes loss of clarity and colour. As above, avoid if you have better options. Here is the guilty party

3) Svideo - (I am gonna say this once only, if you EVER, DARE, IN MY PRESENCE, to call this super-vhs and super-video I will use this on you. Repeatedly. Sure, some vhs machines did have svideo connectors, and they were super-vhs machines, BUT THE CONNECTOR IS CALLED SVIDEO. kappish? Svideo is a 4 wire system, 2 ground, a luminance and a chrominance wire. This is better than composite, at least everything isnt squashed into one wire anymore, and for the most part people can get along with svideo on normal sd crt tv's quite fine. The connector is keyed and can only be inserted one way correctly, but this hasnt stopped people from squashing it in wrong and mashing the pins. This wont help your picture quality, by the way.
A stunning example is here, dressed in black

4) RGB (red, green, blue...like magic) - Ok, we are onto the better stuff now. RGB has seperate wires for the three colours, and then normally a h-sync wire (horizontal sync) and a v-sync (vertical sync) (or sometimes only a c-sync, composite sync). Guess what, this is what your average old computer monitor uses in the vga connections. On a tv, the frequency is much lower, so they cant be swopped willy-nilly, and rgb shouldnt be interchanged with vga, but the concept can be likened to brothers. Most of the time rgb is implemented on a scart connector. Yes, I said scart connector. It is a connector, not a signal type. SCART can carry composite, or rgb, or svideo +audio and syncing/switcing/voltages, or combinations thereof. Picture here

5) Component (sometimes called YPrPb) - this is some good stuff here. Can carry hi-def signals, 3 seperate rca style jacks, colour coded so you cant really mess things up. One red, one green, one blue. No, they dont carry red green and blue data. Use these if you got 'em and nothing better spare..

6) vga - an analog connector - like your computer monitor uses, this is a 15 pin d-sub port, carrying rgb and sync signals. plug your computer into this jack if it is your lowest common connector

7) dvi/hdmi - very similar jacks...all digital and used for modern equipment, hi-def cable/satellite boxes, computers, xbox 360/ps3 etcetera. the hdmi port differs from dvi in that it carries the same data as a dvi port and in addition can carry audio. You can buy dvi-->hdmi cables pretty cheaply. Dont bother about super duper high quality cables, the picture will look the same...the only diff is the more expense cables may have better connectors, better strain relief and perhaps more robust shielding.

Ok, hope that helps clarify the waters a bit, and heed the super-vhs warning. I rarely kid aroudn when I got fresh batteries :-)