The exclamation mark is a device used to distinguish exclamations from statements in written English. An exclamation is a statement of very strong emotion or surprise. For example:
That’s crazy!
You did a great job!
I spent five weeks on that paper and got a C!
It is important to use exclamation marks after sentences that are not questions but begin with question words like ‘how’ and ‘what.’ For example:
How kind of you!
What a day!
How beautiful that sound was!
Without the exclamation mark, the statement may be interpreted as sarcastic. In spoken English, an exclamation is identified by the speaker’s tone of voice. In writing, this distinction is not available; exclamation marks are the punctuation responsible for conveying tone and feeling in written English.
Generally exclamation marks are only used in casual writing; the punctuation does not lend itself to academic writing, which focuses more on facts than personal feelings. In casual applications, exclamation marks are not used with other punctuation marks except in the rare case of the interrobang. An interrobang is the use of a question mark and exclamation mark together. For example:
“You did what?!”
“How dare you?!”
“What on Earth?!”
This combination of punctuations expresses both a direct question and the speaker’s experience of shock.
Exclamation marks have become a popular image on signs. Warning tags often bear the punctuation to bring attention to electric shock hazards. It is also used on signs that instruct the viewer to be alert.