How can a computer connected to a TV to use?

It would depend on if the TV can even accept and process the signal sent from the computer, but if you are asking about what cables and ports that could be used, off the top of my head I would say s-video, D-SUB, dvi and HDMI.

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agree with Lothdk.

you dont say what card you have or what connections you have available to use but the easiest way to connect the two would be HDMI.

Agree with the above. It can be connected by any video out to video in that you have, but if you want audio too, HDMI would be the simplest.

It really does depend on your graphics card (integrated or not). Most modern TVs and modern computers will have some way to connect it - even if you need an adapter.

1, you must have a TV with a VGA port, then you just bought a VGA to RCA / S-Video Adapter Cable
2, if the TV not with a VGA interface, you also could use a PC TO TV Converter.

Why would you need a TV with a VGA port if you could use HDMI out of the computer (if it has a HDMI port)?

Yes, VGA would display it - I've done it a number of times, but HDMI will do both video and audio.

and VGA sucks at signals. that standard should have been killed of years ago, when we moved from CRT to TFT.

Terrible terrible standard.