Cormac McCarthy, author of The Road, No Country for Old Men, and Blood Meridian says of punctuation:
"James Joyce is a good model for punctuation. He keeps it to an absolute minimum. There’s no reason to blot the page up with weird little marks. I mean, if you write properly you shouldn’t have to punctuate."
He adds: "I believe in periods [full stops], in capitals, in the occasional comma, and that’s it."
Quite simply, McCarthy is sensitive to the way words look on a page -- or, again, in our digital age, on a screen and so forth. No semicolons, no quotation marks. Nothing extraneous -- and nearly everything is extraneous. Depending on the venue for which you're writing, you should adjust your sensitivity accordingly.
Ultimately, word choice and, to a surprising extent, punctuation can be a matter of a writer's writing style. For example, I find that in casual writing the semicolon is often unnecessary, and worse, takes on a nearly-pretentious air. No need for that.
In more formal settings, including this course -- though the tone is conversational -- semicolons can help clarify the relationships between thoughts. Generally, we use the semicolon to separate two distinct phrases that are closely related; they could stand alone with full stops, but we signal their closeness with the semicolon. Note well: The semicolon is related to the full stop, not to the comma.
When writing for online publications, including a course such as this, we favour shorter paragraphs than when writing for traditionally-printed publications. Especially in educational settings, we aim for clear, concise ideas broken into brief chunks.
Consider: students reading this course on the small screen of a phone will have an easier time following the text if they don't have to scroll to see a complete paragraph. Newspaper columnists regularly exercise this sort of diligence, even for their printed medium.
These are aesthetic considerations. In addition to aesthetics, and perhaps more importantly, we should consider accessibility when we decide how to present words to readers. This website uses software called "Moodle" as its platform, and Moodle is designed with accessibility in mind, which means it isn't cluttered with pictures and videos, and should be easily navigated by screen reader software.
So, when thinking about printed words, we think about how they look on the page (aesthetics), and how a reader will "hear" them, given how we present the words. These are structural considerations, if you will; this is about the form that words take. Next, let's consider the content conveyed by the words we choose.