em-dash
Expert on the history, origin, and correct use of the em dash. Use when writing or reviewing code, comments, or data files to avoid em and en dashes, defaulting to never using them and replacing any found with a hyphen (-). Includes strong knowledge of punctuation marks and the proper usage of punctuation characters when writing comments.
Profile →npx skills add github/awesome-copilot --skill em-dash --agent copilot
Same command for any agent — swap --agent for claude-code, codex, cursor.
Weekly change comes from our own snapshots, not the repository page — it measures attention, not adoption.
# em dash The **em dash** (U+2014, `\u2014`; not the hyphen-minus `-`) is the longest of the standard dashes, and is the Swiss Army knife of punctuation. Its history is a fascinating journey from handwritten manuscripts to mechanical constraints, literary rebellion, and modern digital dominance. Here is a breakdown of how the em dash evolved: ## History of the em dash ### Early Beginnings (15th-18th Century) - The First Dashes: Early appearances of the dash in English literature date back to 1580 in private letters and 1588 in English drama. They were often used to indicate pauses, self-interruption, or an unfinished thought - Gutenberg and Early Printing: The em dash officially emerged as a standardized typesetting mark during the 15th-century printing revolution #### The Etymology - The "M" Width: The em dash is named because its standard length is equal to the width of the capital letter "M" in the specific typeface being used (Similarly, the slightly shorter en dash is the width of the letter "N") ### Literary Popularity (17th-19th Century) - The Author's Tool: By the 17th and 18th centuries, it became a beloved tool for writers mimicking the natural lurches, stutters, and rhyt
- History of the em dash
- Early Beginnings (15th-18th Century)
- Literary Popularity (17th-19th Century)
- The Typewriter Era (19th-20th Century)
- The Digital Age (Present Day)
- Analysis of em dash History
- When to use em or en dashes
- In Code Files
- In Raw Data and/or Text Files
- Other Punctuation Characters
- End-of-Sentence Marks
- Pauses and Clause Connectors
- Words, Quotations, and Possessions
- Dashes and Slashes
For en dash and em dash
echo - | sed "s/-/-/g"
Replace Unicode en dash (U+2013) and em dash (U+2014) with hyphen-minus (-)
perl -CS -pe 's/\x{2013}|\x{2014}/-/g'
For encoded characters
echo � | sed "s/�/ /g"
perl -CS -pe 's/\x{FFFD}/ /g'What does the em-dash skill do?
Expert on the history, origin, and correct use of the em dash. Use when writing or reviewing code, comments, or data files to avoid em and en dashes, defaulting to never using them and replacing any found with a hyphen (-). Includes strong knowledge of punctuation marks and the proper usage of punctuation characters when writing comments.
How do I install it?
Run `npx skills add github/awesome-copilot --skill em-dash --agent claude-code` — it drops the skill into your project so the agent can pick it up. Swap the --agent value for codex, cursor or copilot if you use one of those.
Where does this skill come from?
From github/awesome-copilot, a repository with 37,432 stars. We read it straight from the repository tree rather than a submitted listing, so what you see here is what is actually published.
Is a popular skill a good skill?
Not necessarily. Stars measure attention, not adoption — a repository can trend for a week and be abandoned. That is why we show the weekly change from our own snapshots next to the total, instead of a single flattering number.