In Java programming, an object’s state is stored in fields, which are not declared with the static keyword. These fields are also known as instance variables, as their values are distinct for each instance of a class or object.

Class variables are fields declared with the static modifier, indicating that there is only one copy of the variable in existence. For example, a field that specifies the number of gears for a specific type of bicycle could be designated as static, as the same number of gears will be applied to all instances conceptually.

Local variables are similar to fields, but they are only visible to the methods in which they are declared and not accessible to the rest of the class. Parameters are consistently classified as “variables” rather than “fields,” and this is true for other parameter-accepting constructs, including constructors and exception handlers.

General guidelines will be used in the discussion of fields and variables for the remainder of this tutorial. “Fields” may refer to “fields in general” (excluding local variables and parameters), while specific terms (static field, local variables, etc.) will be employed when the context requires a distinction. The fields, methods, and nested types of a type are collectively referred to as its members.