PUNK-tu-a-shun

The chart below describes the repertoire of sound you have at your disposal. The rules, strictly speaking, can be found elsewhere. You can look them up. Here, I aim only at what these marks do to the relationship between sound and sense in your writing. Learn to hear them in your head. They are yours to use. Modulate your sound, control your voice. Own them.

Mark / name / musical effect
. / Period / A full stop. The end of a thought. Unless indicating an abbreviation, in which case you still sound out the whole word.
, / Comma / A pause, kinda short. Separates thoughts, elements in a series, so the ear can sort them. The voice pauses and resumes slightly higher.
; / Semicolon / Longer pause than a comma; it indicates a connection between sentences. It can take the place of a conjunction; or it can supplement a conjunction, reinforce it. It forbids aural confusion in lists, such as when the elements contain punctuation themselves: lists; dates, names, or quotations; phrases, elements, objects. In such cases, it changes the aural links.
: / Colon / Simply, “Hey, check out what follows”:  a colon draws attention to another sentence, fragment or list, getting attention off everything to its left, on to everything to its right. It creates a lilting pause right before it.
… / Ellipses / A dropping voice…something indicating hesitation…like an interruption, or thinking time…uncertainty. Also indicates an absence, as when something is removed from the middle of a quotation (see bracket for more).
-- / Dash / Drama—a clean break in tone. It’s like a colon out loud—not that colons are quiet—but bolder. It also forwards what might’ve been parenthetical elements, keeping the voice high. Indicated by two joined hyphens, but longer dashes indicate more drama.
( ) / Parenthesis / An aside (as in Shakespeare, they can convey secret, very important info, whispered) that moves alongside the main body of the sentence. (They can also make such info stand on its own, by the way.) Lower.
(( )) / Double Parenthesis / Even lower (meaning an aside within the aside ((but don’t overdo it—the effect is slightly comical)), slowed down and very, very quiet), set off from the rest of the sentence.
[ ] / Bracket / Dead silent. Noticed but not sounded, they are editorial comments, indicating changes ([such as] omissions ((which use ellipses in brackets like so: […])) or grammatical smoothing) you added to the original text. Also a “mistak [sic] in the quoted text,” “sic” used here means, “I found it this way.”
“ ” / Quotation Marks / Voice raises after a pause, taking on the sound of the speaker. You are acting in your text, using someone else’s voice to “say something” for you. Can also indicate sarcasm or so-called “irony.” They open and close quietly, but with strength, up and down pointing, read “: open quote, ”: close quote.
‘ ’ / Single quotation / Subtle in sound, used to quote within a quotation: “Like the man said, ‘Don’t go crazy with it!’.” Your voice has to go up and down as you go, following the speaker within the speaker. European writing reverses the use of doubles and singles, just to mess with your head.
? / Question mark / The obvious, of course; but also uncertainty (hesitancy?). Always there’s a lilt at the end, and it can change a declaration into a blubbering mass of wha…?
! / Exclamation Point / Voice gets louder. A one-shot item. Never use more than one. Leaving it out of an interjection (like, “Crap!”) can be just as important, indicating a flat tone or irony very different from “”. Crap. And always use it alone! Don’t use it too much! It gets tired! And so does your reader!
italics / Emphasizes any word in a sentence and changes its meaning. Emphasizes the word I say. Emphasizes the word, do you hear? Also, indicates something published on its own, like a novel, long poem, movie, album, etc. Gives it more space. Used instead of underlining, the voice hovers over it. [I hope I don’t forget to include that it can indicate internal thoughts, or stage directions, for the reader.] Don’t overuse it this way. It’s not strictly academic. It also indicates a different language, so you have to pronounce the word (logos) in the right way.
- / Hyphen / Runs words together, making them one, smushed-like, quick-footed on the page. Use it when you use two words to describe something as if they were one. But you don’t use it with -ly; it’s quickly moving sound makes that sound awkward.
/ / Slash / Say “slash.” Strangely, we seem to actually pronounce it. It’s a punctuation/explanation. Indicates slowly articulated alternatives/relations in a sentence. “Also indicates a break of some kind / As in the ending of a line / Of a song or poetry.”
’ / Apostrophe / Smushes and speeds like a hyphen, but indicates missing letters or numbers. It’s like a shortcut, informal, conversational, friendly. It is not used with the pronoun “it” (which distinguishes it from “it is”) and its absence indicates a certain formality of tone you cannot ignore. It’s about speed and clarity. Oh, yeah--and possession. It indicates that, too.
* / Asterisk, note / You have something to say that’s tangentially related to what you’re talking about.[1] It’s silent, but can make a huge break for the reader who looks below.

[1] This can include documentation, but it also can just be additional stuff. I’m speaking, of course, of a footnote. But I didn’t want to interrupt the form of my fine graph to say that if you use more than one a page, you must use different marks, like these: † or ‡. But if you’re using a bunch of them, you need to use numbers. You also can put the info on the last page, in which case they’re called endnotes (logically enough). These comments are a little quieter, can be fun, or even annoying if they go on too long—that can be serious, or seriously comic. Incidentally, blank space on a page also has an effect similar to punctuation—breaks in sections in a long paper, for instance; or setting a quotation off in the middle of a page for drama. You must, with this and all these tools, follow the golden rule of moderation.