In the United States, we use single quotation marks [ ' ' ] to enclose quoted material (or the titles of poems, stories, articles) within other quoted material:

• "'Design' is my favorite poem," he said.
• "Did she ask, 'What's going on?'"
• Ralph Ellison recalls the Golden Age of Jazz this way: "It was itself a texture of fragments, repetitive, nervous, not fully formed; its melodic lines underground, secret and taunting; its riffs jeering—'Salt peanuts! Salt peanuts!'"

British practice, again, is quite different. In fact, single-quote marks and double-quote marks are apt to be reversed in usage. Instructors in the U.S. should probably take this into account when reading papers submitted by students who have gone to school in other parts of the globe.

In newspapers, single quotation marks are used in headlines where double quotation marks would otherwise appear.

• Congress Cries 'Shame!'

In some fields, key terms may be set apart with single-quote marks. In such cases, periods and commas go outside the single-quote marks:

• Sartre's treatment of 'being', as opposed to his treatment of 'non-being', has been thoroughly described in Kaufmann's book.

When the term is case-sensitive, capitalization remains unchanged despite placement in the sentence.

• 'tx_send' determines whether the signal will be output through TX Output Port.
• If the constant REG_RESET is set, then resets will be registered.