The navy had two kinds of airships. Limp and rigid. (Keep the viagra jokes here to a minimum)
The limp variety had two sub types. the A-Limp airship and the B-Limp airship. B-Limps became blimps.
A blimp is a airship that uses gas pressure to keep shape, much like a shaped hot air balloon, but with internal air bladders to keep pressure.
A dirigible uses a rigid frame within the envelope for structure. The Macon was a dirigible.
<< after closer scrutiny, it look as though the a-limp and b-limp may be a legend. Some say the blimp was a spelling out of the sound that the skin of a blimp makes when you punch it.
