Jargon

Jargon is terminology used by experts for experts; that is, words and phrases used to communicate within a particular field. When writing for other experts, jargon is essential. Without jargon, you'd be perpetually redefining ideas that your readers already understand. With jargon, you can just blurt out, "capacitor," and assume that your electrical engineer readership will know exactly what you're talking about.

The hard part to remember is that your lay audience does not speak jargon. (Hey, that's what makes them the lay audience in the first place.) Frequently, jargon is so ingrained in the way you speak, think, and write, that you no longer perceive jargon to be jargon. For example, my wife asked me if I could put some images on the Web (itself jargon only four or five years ago) for her, and I asked if the images were GIFs or JPEGs. GIFs and JPEGs are useful terms around the office, but completely useless around my dinner table.

Some words bob up and down between jargon and general use. Many words fall into that gray area. When in doubt, assume that it is jargon.