So yeah, why?

The prime lens I got was kindly shipped with a few. How do I choose among them?

UV/Have (Sometimes called "skylight") - use if you are in the mountains, or doing aerial photography (or if it really is a hazy day, and you want to reduce some of that).

Circular polarizer - reduce some types of reflections, increase internal contrast, darken skies.

Netural density - depending on density can be helpful in limited circumstances (wishing to use a longer shutter speed to get water blur, or wanting to use a wider aperture than you otherwise could in bright sunlight).

Most anything else is probably more geared towards specialty use, or b&w film photography (these would be yellow, red, green... etc.)

Ah the filters that came with the lens are colors. I didn't understand, but now that I know they're for black and white, I think I get it.

You have been so patient and kind with all the questions.

THANKS!

No problem.

Yah, with BW film, color filters are handy (you can mimic the effects with the color channel mixer in Photoshop). If you imagine photographing two bell peppers, one red and one green - both would be nearly teh same shade of grey, shot straight. Use a red filter and the red pepper turns nearly white, the green pepper, nearly black...

Useful for darkening skies to show clouds better, changing foliage's apparent darkness, affecting skin tones (red filters will help hide freckles and pimples, lightening them) ... etc.