word choice - Is it supposed to be a HTML or an HTML

I've seen many people who say:

This is a HTML page.

Yet I've also seen many people who say:

This is an HTML page.

Are both usages equally correct?

Or, which is the grammatically correct one?

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Possible Duplicates:
“A” vs. “An” in writing vs. pronunciation
Do you use “a” or “an” before acronyms?

Answer

It depends on whether you say aitch or haitch.

• An aitch tee em el page


• A haitch tee em el page