Java Basic 3-Introduction to Data Types

Java has two categories of data:
Primitive Data Type: such as boolean, char, int, short, byte, long, float and double
Non-Primitive Data Type or Object Data type: such as String, Array, etc.
Primitive Data Type
Primitive data are only single values and have no special capabilities.

There are 8 primitive data types:

boolean: boolean data type represents only one bit of information either true or false, but the size of boolean data type is virtual machine-dependent. Values of type boolean are not converted implicitly or explicitly (with casts) to any other type. But the programmer can easily write conversion code.
Syntax: boolean booleanVar;
Size:virtual machine dependent
Values:true, false
Default Value:false

The byte data type is an 8-bit signed two’s complement integer. The byte data type is useful for saving memory in large arrays.
Syntax:byte byteVar;
Size:1 byte ( 8 bits )
Values:-128 to 127
Default Value:0

short: The short data type is a 16-bit signed two’s complement integer. Similar to byte, use a short to save memory in large arrays, in situations where the memory savings actually matters.
Syntax:short shortVar;
Size:2 byte ( 16 bits )
Values:-32, 768 to 32, 767 (inclusive)
Default Value:0

int: It is a 32-bit signed two’s complement integer.
Syntax:int intVar;
Size:4 byte ( 32 bits )
Values:-2, 147, 483, 648 to 2, 147, 483, 647 (inclusive)
Default Value:0

float: The float data type is a single-precision 32-bit IEEE 754 floating point. Use a float (instead of double) if you need to save memory in large arrays of floating point numbers.
Syntax:float floatVar;
Size:4 byte ( 32 bits )
Values:upto 7 decimal digits
Default Value:0.0

char: The char data type is a single 16-bit Unicode character.
Syntax:char charVar;
Size:2 byte ( 16 bits )
Values:'\u0000' (0) to '\uffff' (65535)
Default Value:'\u0000'