Addition is one of the four basic operations, which refers to the calculation of combining two or more numbers and quantities into one number and quantity. The symbol of addition is the plus sign "+". Connect items with a plus sign when adding.

Addition (usually indicated by the plus sign "+") is one of the four basic arithmetic operations, and the others are subtraction, multiplication and division. For example, in the picture below, * * * has a combination of three apples and two apples, and * * * counts as five apples. This observation is equivalent to the mathematical expression "3+2 = 5", that is, "3 plus 2 equals 5".

In addition to calculating fruits, you can also calculate other physical objects. Using system generalization, addition can also be defined on more abstract quantities, such as integers, rational numbers, real numbers and complex numbers, and other abstract objects, such as vectors and matrices.

In arithmetic, the addition rules involving fractions and negative numbers are designed.

Addition has several important properties. It is interchangeable, which means that the order is not important, it is interrelated, which means that when more than two numbers are added, the order in which the addition is performed is not important. Repeatedly adding 1 is the same as counting; Adding 0 will not change the result. Addition also follows related operations such as subtraction and multiplication.

Addition is one of the simplest digital tasks. The most basic addition: 1+ 1 five-month-old babies and even other animal species can be counted. In primary education, students are taught to calculate the superposition of decimal numbers, starting with one digit, and gradually solving the more difficult number calculation. The number system in general addition is called addend, and the result is called sum; Addition is to transfer so many addends into sum. This is different from the factor to be multiplied. In fact, during the Renaissance, many writers did not consider the first plus sign at all. Today, due to the nature of bonus exchange, "cannon" is rarely used, and these two terms are usually called addend.

All the above terms come from Latin. "Add" and "add" are English words derived from the Latin verb addere, and the latter is "original"-that is, "ad" and "; So supplement is to give. Using the gerund suffix -nd leads to "addend" and "something to add". Similarly, from the perspective of "increasing", one is "strengthening" and the other is "adding things".

"Sum" and "sum" come from Latin nouns "highest, highest" and related words. Because the upward trend in ancient Greece and Rome is contrary to the modern downward practice, one number is higher than the addend. Plus sign "+"(Unicode: u+002b; ASCII:+) is the abbreviation of Latin "et", which means "and". It appears in mathematical works dating back at least to 1489.