The invention of numbers is not credited to one individual but is believed to have developed when ancient civilizations began to trade and individuals needed a way to count the materials they traded, as well as the compe... More »

The zero symbol first appeared around 2000 B.C. when the ancient Babylonians used it to mark that something was missing. As a concept and a number, however, the zero was invented in India around 650 B.C. More »

The concept of zero first appeared in A.D. 976. The Persian encyclopedist Muhammad ibn Ahmad al-Khwarizmi observed that if no number appeared in the tens place, then an empty circle represented a placeholder. However, th... More »

A numeric order is a way to arrange a sequence of numbers and can be either ascending or descending. For example, an ascending numerical order of area codes for the United States starts with 201, 203, 204 and 205. More »

Generally, people should write numbers out the way they sound. For example, 2,345 could be written as "two thousand three hundred forty-five." When writing numbers out for a check, hyphenate numbers between 21 and 99. Al... More »

Binary numbers are a way to represent numbers using only zeros and ones. The binary system can also be called the base-2 system as each number place is equal to two to the power of that place. More »

The invention of the ruler dates back to ancient civilizations, such as the Greeks and Egyptians. Used to make measurements in a straight line, the first excavated rulers were often made from wood or ivory. More »