Difference Between Digit and Number

数字与数量

Difference between a digit and a number is similar to the difference between a letter or a character and a word. Just like alphabetical letters make words, digits make numerals, which is a representation of a number.

Numbers

Many years before, ancient people needed to count objects. Therefore, numbers were introduced for counting and measuring purposes. During earlier days, they needed only whole numbers. Later on, rational numbers were introduced. In modern mathematics, we talk about different categories of numbers, such as real numbers, complex numbers, rational and irrational numbers etc.

Modern people needed to keep written records on quantity of things they owned, stored or sold. So, they needed a convenient and standardized system of symbols to represent numbers. Such a system of symbols is called a numeral system. During the last thousand of years, different numeral systems were introduced, and Hindu-Arabic number system is the most commonly used in today’s mathematics. Hindu Arabic number system is a decimal placed value system that consists of ten symbols; 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9.

Digits

每个符号in a numerical system is also called a digit. A number can represent as number word or a combination of digits. A digit is a single symbol in a numeral representation of a number. A digit can have both the place value and a face value. Both 1 and 123 are numbers. 1 is a single digit number, but 123 is a 3 digit number. Value of a number is unique. For an example 5, 55,555 have their own numerical value. But a value of digit can be different under the position it exists. In other words, a digit holds a position value.

What is the difference between Digit and Number? · Numbers are made up of digits, and digits make numbers. · A digit is a symbol, and number may consist of one or more digits. · A number has a numerical value, while digit is just a representation.