Just to add a bit of fuel to the fire, many people incorrectly use the article "an"
incorrectly with many words that begin with "H."  This may be grammatically correct
in some countries, but, in the United States, the rule is that if the "H" is silent, use
"an" just as if the word actually began with a vowel, such as "an hour."  If the "H" is
pronounced, us the article "A," such as "a historian."

Enjoy,

Bill