Primitive Data Types in Java

double

8 bytes - Stores fractional numbers. Sufficient for storing 15 decimal digits.

long

8 bytes - stores whole numbers from about -9.2 quintillion to 9.2 quintillion

boolean

1 bit - Stores true or false values

byte

1 byte - stores whole numbers from -128 to 127

char

2 bytes - Stores a single character/letter or ASCII values.

short

2 bytes - stores whole numbers from about -32k to 32k

float

4 bytes - Stores fractional numbers. Sufficient for storing 6 to 7 decimal digits

int

4 bytes - stores whole numbers from about -2.1 billion to 2.1 billion