It's definitely a good idea to learn the terminology of the business. A query letter is nothing more than a BRIEF letter of introduction, maybe going something like this:

To Whom It May Concern:

By way of introduction, my name is Karri and I'm a professional (landscape, portrait, etc.) photographer.
After reviewing your product line, I feel that my work may fall within (company name's) corporate vision.
Could you please send your submission guidelines for photography, including your various methods for image delivery, at your earliest convenience.

Thank you.

Sincerely,
Karri
karri@karri.com