Basically titles, captions and credits can be static, roll up the screen or crawl horizontally across the screen, usually at the bottom. Be careful those that are static stay on sufficiently long and those that crawl and roll do so sufficiently slowly to be easily read.

If you are placing titles or captions over a static or moving image make sure that all the text is over a dark background so that nothing is lost.

Equally be careful your title does not obscure some vital information in the picture.

Choose the typeface carefully. The best are often modern ones that are plain, bold and with strong clean lines. 'Old English' and 'Copperplate' often don't work well even if they are appropriate to the subject.

Because of TV's problems of picture definition and horizontal scan lines, some typefaces will be hard to read. Avoid those with fine lines, which may break up, and condensed type that may fill in.

Be cautious of mixing typefaces unless you have some training in typography ie., the typefaces you use for titles, captions and credits should at least be very similar, if not the same, and you really need to know what you are doing if you want to use different typefaces for individual letters in a word.

Your titles or credits do not need to be dead centre. They can be placed anywhere within the screen and of the right size for the style of video you are making. If you are making-up your own titles(eg using Letraset or magnetic letters) make sure they will fit the 4:3 aspect of the TV screen or 16:9 in widescreen.

Titles are OK in capital letters. Captions and credits in upper and lower case are easy to read and, in the case of captions, do not obscure too much of the image. Credits look neat in blocks with 'roles' ranged left and 'names' ranged right eg: