I have come across examples supporting both spaced as well as non-spaced examples and that's what confuses me. I want to understand what the standard practice is as endorsed by any of the major style guides. For example, consider the following examples:
A. B. Smith (Why is there a space?)
U.S.A (Why no space? And why no period after the "A"?)
P.S. (Why no space?)
I understand there already exists a similar question but since the answers on that one specifically deal with academic citations and Latin phrases, it doesn't help me. I am comfortable with Latin phrases, such as e.g., i.e., etc. not having spaces (P.S. being an exception because I still somehow see it as a regular abbreviation because it's capitalized, maybe. I don't know). It's the English acronyms that I find confusing…especially cases like U.S.A where even a period (the last one) is sometimes mysteriously omitted!
Best Answer
The reason there is a space here is because that is a person's name initialized. There are usually spaces between those, though it is up to that person how they prefer their name to appear.
First, U.S.A. almost always has a period after the "a". If it doesn't, it's usually spelled "USA" (with no periods at all). Between just the first two is improper grammar. It's becoming more and more common to leave out spaces in the middle of abbreviations and acronyms.
P.S. has no spaces because it's a single word: postscript.