Become an intermediate level Java developer, ready to take on your own projects.

Become a Spring Boot Developer

Learn Java for free with this interactive module, and get a handle on one of the most popular programming languages in the world.

You'll start with a simple hello world program and proceed to cover common concepts such as conditional statements, loop statements, math, and logic in Java, before moving on to more advanced concepts like inheritance, generics, and ArrayLists, along with much more.

Core Java Concepts

# Numeric data types

This classification contains all data types that are numeric. 

>    **Did you know?**\
> Variable Types are more often referred to as **"Data Types"**.
 
## Integer

An *integer* is a whole number; that is, it does not have any decimal places. Examples of an integer include **4, 5, 2000**, whereas numbers that are not integers include **4.3, 4.55**. 

Within integers, there are different data types that are based on the space they take within memory. The types include `short`, `int`, and `long`.




// A short type is a 16 bit signed integer
short age; // Stores from +32,767 to -32,768	

// An int type is a 32 bit signed integer
int age; // Stores from +2,147,483,647 to -2,147,483,648

// A long type is a 64 bit signed integer
long age; // Stores from +9,223,372,036,854,775,807 to -9,223,372,036,854,775,808

>**Note:** Data types in Java are all signed. This means that they can store positive as well as negative values of integers. 

## Floating points

This data type stores numbers that include a *decimal point*. Hence they will include numbers like **4.34** or even **12233.333922**. Keep in mind that floating points will only store an approximation of the decimal value and not the *exact* value. 

Floating points have two types, `floats` and `double`. The primary difference between the two is that `double` is able to store more places after the decimal point more accurately than `float`. The `float` data type is fine for most applications. But, scientific applications that deal in really small values like the radius of an atom or really large values like the distance between two galaxies are more amenable to using `double`.




In this lesson, we will discuss primitive data types in Java.