Allan Poe Rules for punctuation vary with the language and with the country. In American English, a space follows a punctuation mark, but no space precedes a punctuation mark. Although acronyms and abbreviations are common in newspapers, they usually are not desirable in formal writing. If you use a lot of abbreviations, you are committing the error of assuming that your audience knows everything that you know. Every field of study has its own jargon.
Specialized terminology can lend precision, but it also limits accessibility to outsiders.
Be aware that punctuation may have semantic content. Consider the following two sentences. Students who like mathematics are friendly. Students, who like mathematics, are friendly. The first sentence qualifies the subset of those students who happen to like mathematics.