How to Use Em Dashes (–), En Dashes (–), and Hyphens (-)

Perceived importance of dash distinctions

• Some see em/en dashes and hyphens as basic literacy that “used to be drilled in school”; others say it’s now a niche concern due to declining instruction and awkward keyboard support.
• A sizable group explicitly refuses to care, using only the ASCII hyphen for everything and arguing it rarely harms comprehension.

Keyboard support and input methods

• macOS: built‑in shortcuts (Option‑hyphen for en dash, Option‑Shift‑hyphen for em dash) are widely praised; many other symbols are similarly grouped mnemonically.
• Windows: options include Alt+0151, the emoji/symbol picker (Win+.), PowerToys, AutoHotkey, and third‑party compose tools.
• Linux/Xorg: compose key sequences (e.g., Compose‑‑. → en dash, Compose‑--- → em dash) are common.
• Office, Google Docs, iOS, LaTeX, Markdown, and smart-quote–style “smartypants” tools have long auto‑conversion rules (e.g., “--” → em dash), which complicates any attempt to infer authorship from punctuation.

Em dashes as an “LLM tell”

• Many commenters claim overuse of em dashes—especially in casual web text—is a strong indicator of LLM output; some now avoid them or introduce typos to “sound human.”
• Others strongly dispute this: professional and typographically aware writers, editors, academics, and LaTeX users report long‑standing correct dash usage pre‑LLM.
• Several note that auto‑substitution in word processors and phones plus professional training data make em dashes a weak or biased signal; precise writing by students or autistic kids has reportedly been misclassified as AI.

Style, spacing, and regional conventions

• Rules of thumb repeated: hyphen connects (compound words), en dash marks ranges (dates, pages, number spans), em dash breaks thoughts or sets off clauses.
• Disagreement over spacing: books/journals often “closed” em dash (no spaces); AP and many British styles prefer spaced en dashes – like this – instead of em dashes. Some advocate thin or hair spaces as a compromise.
• Debates extend to page‑range shortening (128–34 vs 128–134) and whether that’s clearer or confusing.

Extended typographic and Unicode concerns

• Discussion of the dedicated minus sign (−, U+2212), figure dash (‒), figure space, smart quotes, ellipsis (…), and even CJK “one” and vowel‑elongation marks.
• Some argue these distinctions aid clarity and aesthetics; others see them as pedantic or fragile in plain‑text/monospace and data-processing contexts (CSV, financial software).