what does s substring mean in java code example

Example 1: java substring

String s = "Let's Get This Bread";

String subString = s.substring(6, 9);
				// (start index inclusive, end index exclusive)

// subString == "Get"

Example 2: substring java

import java.lang.*;

public class StringDemo {
public static void main(String[] args) {
String str = "This is tutorials point";
String substr = "";

// prints the substring after index 8 till index 17
substr = str.substring(8, 17);
System.out.println("substring = " + substr);

// prints the substring after index 0 till index 8
substr = str.substring(0, 8);
System.out.println("substring = " + substr);
}
}