That depends on the 'source', the format the music or picture is in at the moment. You might need to convert that to another format, if it isn't the same as the it should be on the cd/dvd (both are very well standardised, so are rather picky about what that format must be).
For the most common video formats, you can use DVD Flick (free) to make an image of a DVD, that you can burn to the final disk using, for example, IMGBURN (free).
If the audio is a .wav file, the burning program that came with your burner (such a Nero) or a third party program like CDBURNERXP (free) have an option to 'burn an audio cd'.
Kees
how do I make a dvd/cd on my pc that plays on other players

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