1 00:00:00,060 --> 00:00:03,130 ‫We have understood how to run a Java program. 2 00:00:03,720 --> 00:00:07,260 ‫Why don't we take a closer look at the program that we've written? 3 00:00:07,920 --> 00:00:11,760 ‫The Hello World application consists of two primary components. 4 00:00:11,910 --> 00:00:18,800 ‫First, the hell a world class definition and the main method, public class. 5 00:00:18,810 --> 00:00:22,530 ‫Hello, world is the first line of our Java program. 6 00:00:23,400 --> 00:00:30,570 ‫Every Java application must have at least one class definition that consists of the class keyword, 7 00:00:30,570 --> 00:00:32,430 ‫followed by the class name. 8 00:00:33,640 --> 00:00:39,340 ‫And the code for each class appears between the opening and closing curly braces. 9 00:00:40,400 --> 00:00:46,610 ‫Now we will discuss the subject of classes in further detail and some of the upcoming lectures, but 10 00:00:46,610 --> 00:00:53,270 ‫right now it's just enough to know that every Java application begins with a class definition. 11 00:00:54,080 --> 00:00:59,610 ‫Public static void main string args or arguments. 12 00:01:00,380 --> 00:01:02,450 ‫So this is our next line in the program. 13 00:01:03,660 --> 00:01:10,290 ‫In the Java programming language, every application must contain a main method whose signature is, 14 00:01:10,290 --> 00:01:11,340 ‫well, just like that. 15 00:01:11,790 --> 00:01:17,220 ‫Also will cover how to define a method in Java and the next upcoming lectures. 16 00:01:18,410 --> 00:01:23,450 ‫And then finally, line system got out dot print lekan. 17 00:01:24,440 --> 00:01:32,930 ‫Hello, world, so the print method prints the contents inside the double quote into the console and 18 00:01:33,170 --> 00:01:39,560 ‫inserts a new line after, so it uses a system class from the core library of Java. 19 00:01:40,430 --> 00:01:44,990 ‫Now, don't worry, if you don't get it at first, we're going to learn a whole lot more about classes 20 00:01:44,990 --> 00:01:47,480 ‫and methods in the next lectures.