Learn English – Difference between “jargon” and “technical terms”

In his classic book, The Careful Writer, Theodore Bernstein has an entry on inside talk, in which he includes the subclassifications of: argot, jargon, lingo, and slang. He states (p. 237):

The reason that all these words have disparaging connotations is that outsiders dislike being outsiders. They envy or resent those who can speak and understand inside talk. And in some instances the very desire to keep outsiders out accounts for these languages...There is a tendency in specialized groups, for reasons of either establishing a kind of mystic bond or asserting a kind of self-importance, to employ esoteric or pretentious words... This is by no means to say that all inside talk, all jargon, is pretentious and useless. On the contrary, most of it is highly necessary. Those in specialized fields have a need to communicate with one another in precise terms and with an economy of expression. A single word will often convey to a colleague what would require a sentence, a paragraph, or perhaps an even longer description to convey to a layman. The fact that the layman does not comprehend the single word does not indict it for use within its proper sphere...

A final caution may be of value in a discussion of inside talk. In writing intended for general reading, the use, whether by a specialist or by a layman, of jargon terms that are not commonly understood smacks of pedantry. If the writer believes that it is imperative to use such a term, he should at least explain it when it is introduced. It must never be forgotten that the function of writing is communication.

I believe the term jargon has come to mean technical terms used to exclude outsiders to a field. I think you could say that it is the intent of their use that separates jargon from technical terms.