what do the sizes on lens mean?

[furnic]

so ok, due to some extra load shedding finally had the time to play with my olympus slr and read the manual back to front- sheez.
anyhow, besides been blown away by how much these cameras can do, what exactly do the numbers on a lens mean?
The current lens I have is 14mm - 42mm, but what do the numbers mean?
For example I am looking at doing more Macro photos - so the lens I would need is a 35mm fixed lens? (they also have a 50mm but is costs like more than double) - so what do these numbers mean, thanks in advance.

[bwana]

I have no doubt the technical fundis will have a better answer for you but in short the 14-42mm is the focal length - 14mm giving you a wide angle and on out to a tighter 42mm.

For macro you want to be able to focus on the object when it is closer to the lens. http://en.wikipedia.org/wiki/Macro_photography

(The wiki article refers to a 35mm lens but in this case they mean a macro lens designed for 35mm format film camera)

There are a few ways I can think of that will let you use your existing lens for macro photography - the first is by attaching closeup lens (http://en.wikipedia.org/wiki/Close-up_lens) to the front of the lens and another is by attaching an extension tube (http://en.wikipedia.org/wiki/Extension_tube) to the rear of the lens.

There's also this method if you have a steady hand :D

http://mybroadband.co.za/photos/data//503/medium/macroKit.jpg

You reverse the lens and hand hold it against the body.