Hundred is the number that comes after ninety-nine and represents ten groups of ten, written as 100. When you count to one hundred, you've reached a milestone that feels significant: it's the first three-digit number you encounter.

A hundred appears constantly in everyday life. Money uses it as a basic unit: a hundred cents make a dollar, and a hundred-dollar bill is a common denomination. Temperature scales use it too: water boils at one hundred degrees Celsius. Sports tracks often measure distances in hundreds of meters or yards.

The word has special uses beyond just counting. A century is a hundred years. When something happens a hundred times, it means very many times, though not necessarily exactly one hundred. If you're giving a hundred percent, you're putting in all your effort, holding nothing back.

People also use hundred in expressions like hundreds of people to mean a large but indefinite number, somewhere in the range of several hundred but not precisely counted. The phrase a hundred percent has become shorthand for complete certainty or total agreement: “Are you sure?” “A hundred percent.”