First off, forgive me if I didn't spell tonging right. I don't know how. Anyway, I have heard that for Irish music some people do double tonging. What is that? Is it also used in classical music? If so, when? Can you use it on the oboe too? Thanks!

It' a technique used to produce lots ofsmall notes quickly. Try saying duck-ah duck-ah duck-ah while noting what your tongue does. The reproduce that same tongue action while playing. With practice, you can make hemi-demi-semiquaviers with the best of them!

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Edit: "ofsmall" s/b "of small"
"The reproduce" s/b "Then reproduce"

Try not to say it out loud too much. Doing so will forge a dependency on the sound, and you will not be able to do it well on your instrument.

Dr. Nina Perlove, Flute Professor at Northern Kentucky University has posted many online flute lessons. She has a complete series on articulation and double tonguing in particular. You may find this very helpful.

http://www.youtube.com/results?search_type=&search_query=nina+perlove+double+tongu&aq=f

Thanks!