We know that in the bottom of the computer is completely based on the data, we have prepared procedures for operation data.

Expression is understood to be the number of computers, operator of the joint variables. For example, add, subtract, multiply, divide and so on, this and other languages, the following expressions are

Here we pay attention to language and other differences between the 10 / 2,10 / 2.0 difference, Ruby only when there is a regular expression is float, the result is the floating-point numbers

**0 / 0 would be reported to an exception, but the results of 0.0/0.0 is NaN**

**Negative operation**

**** Operator, power calculation,** as well as the **power of root**

**Joint calculations, from right to left**

**** Priority than high priority +,-,*,/**

**Integer can be very large, but the floating-point numbers can not be greater than Float:: MAX**

**Abbreviated form of x + = y and x = x + y**

**Floating-point**

Because the floating-point values are accurate, so we are approximations, see the following code

The author of this article: Wang water