Java data types

A variable could be declare as one of them.

Name	Description	Syntax	Example
byte	8-bit signed integer	byte <variable_name> = <value>;	byte age = 32;
short	16-bit signed integer	short <variable_name> = <value>;	short year = 2022;
int	32-bit signed integer	int <variable_name> = <value>;	int quantity = 100;
long	64-bit signed integer	long <variable_name> = <value>;	long population = 7000000000L;
float	32-bit floating point	float <variable_name> = <value>;	float price = 49.99f;
double	64-bit floating point	double <variable_name> = <value>;	double interestRate = 0.05;
boolean	True or false	boolean <variable_name> = <value>;	boolean isValid = true;
char	16-bit Unicode character	char <variable_name> = <value>;	char grade = 'A';
String	Sequence of characters	String <variable_name> = <value>;	String name = "John Doe";

Note that when declaring variables of type float, the f suffix must be added to the value to indicate that it is a floating point value. When declaring variables of type long, the L suffix must be added to the value to indicate that it is a long integer value.

Also, String is not a primitive data type in Java, but it is often used as if it were one. A String is actually an object, but Java provides special support for String objects, making it easy to use them in a way that is similar to primitive data types.