Java Chapter II variables

1. What is a variable?

The basic unit of data storage.

2. The data type is divided into:

Basic types and reference data

3. Differences between the basic data type and the reference data type:

Base data: Different variables will allocate different storage space, changing one variable will not affect the other variable

Reference data type: assignment is to pass a reference to the original object to another reference, and two points to the same piece of memory space.

4. Variable name rules:

1. Must start with a letter

2. Can contain numbers but cannot start with a number

3. If the method name is a combination of multiple words, the first letter of the word must be capitalized.

Java Chapter II variables