Java public class HelloWorldApp { public static void main(String[] args) { System.out.println("Hello World!"); } } Java: Terminal, Compile, Run Operators Data Types Data conversion Functions main() re-try-catch() Loops while, do while Data type String Collection data types Multidimensional Arrays type[][] List<Type> HashMap<<Key>, <Value>> Data Conversion System System: Env Runtime Unit Testing Frameworks TestNG Maven Maven docs Maven repository Maven