Jargon v/s Slang

Do you know what does it mean "jargon"? According to The Cambridge Dictionary, this word stands for “special words and phrases which are used by particular groups of people, especially in their work.”. This is commonly used by some professions, like policemen or doctors. It's not the same than "slang" as you can read under.

                           Jargon

        Pros                           Cons

• Formality                 Common people wouldn't understand
• Wide Vocabulary    Needs knowledge to use

                           Slang

       Pros                            Cons

• Easy to use                 Informality
• Shorter language       Narrow Vocabulary

Personally, I think slang is always used and I do to, but the big problem about it is the informality. When you are in a formal occasion, you have to beware about what you say, because in any minute you may speak with a slang and it would be frowned up. And the problem with jargon is that not everyone knows it, so you can't talk always with jargon, because nobody would understand you.

Glossary of some Jargons:

http://crime.about.com/od/glpolice/Glossary_of_Police_Terms_Acronyms_and_Jargon.htm
http://www.ruf.rice.edu/~kemmer/Words04/usage/jargon_medical.html