Zero

Also called nought or naught.

How to type it

Right pinky. Introduced in Lesson 21: Numbers: 6 to 0.

Common uses

• Zero means none, and it marks the starting point between negative and positive numbers.
• As a placeholder, 0 is what makes 10 different from 1.
• Midnight on a 24-hour clock is written 00:00.

Less common uses

• Indian mathematicians treated zero as a number with its own arithmetic rules, and Brahmagupta described those rules in the seventh century.
• Many programming languages start counting list positions at 0.
• Roman numerals have no symbol for zero.