Addition is one of the four basic operations of arithmetic, with the others being subtraction, multiplication and division. It is signified by the symbol “+” called the plus symbol. The addition of two whole numbers is the total amount of those quantities combined. For instance, if we combine one block and three blocks together it would add up to a total of four blocks. This observation is equivalent to the mathematical expression “1 + 3 = 4” i.e., “1 add 3 is equal to 4“. Addition is also used to represent combination of other physical and abstract objects, such as real numbers, rational numbers, integers, complex numbers and other abstract objects such as vectors and matrices.