HTML Entity - Em-dash ("us-dash—use Without Spaces")

Mistake: Using two hyphens -- instead of the proper em-dash —

Fix: Use — (—) for em dashes. Using -- is a typewriter convention and looks unprofessional in proper typography.

Mistake: Confusing em-dash — with en-dash –

Fix: The em-dash — is the width of the letter "m" and is used for breaks in thought. The en-dash – is the width of "n" and is used for ranges.

Mistake: Adding spaces around em-dash incorrectly

Fix: In American English, em dashes have no spaces around them (like—this). In British English, they often use spaces (like — this). Be consistent.