NUMERAL SYSTEM

any of various sets of symbols and the rules for using them to represent numbers, which are used to express how many objects are in a given set. Thus the idea of oneness can be represented by the Roman numeral I, by the Greek letter alpha a (the first letter) used as a numeral, by the Hebrew letter aleph (the first letter) used as a numeral, or by the modern numeral 1, which is Hindu-Arabic in origin. Modern numeral systems are place-value systemsthat is, the value of the symbol depends upon the position or place of the symbol in the representation; for example, the 2 in 20 and 200 represent two tens and two hundreds, respectively. Such ancient systems as the Egyptian, Roman, Hebrew, and Greek numeral systems did not have this positional characteristic, thus making arithmetical calculations difficult. The most commonly used numeral system is the decimal-positional numeral system, the decimal referring to the use of 10 symbols0, 1, 2, 3, 4, 5, 6, 7, 8, 9to construct all numbers.