In Java, a random number is a number generated by a program that has no pattern and is not predictable. It is often used to generate numbers for various purposes such as generating unique ids, selecting random elements from a list, shuffling a deck of cards, or creating random data for simulations.

There are several ways to generate random numbers in Java. One way is to use the java.util.Random class. This class provides methods for generating random numbers of different types, such as nextInt() for generating a random integer, nextDouble() for generating a random double, and nextBoolean() for generating a random boolean value.

Here is an example of how to use the java.util.Random class to generate a random integer between 1 and 10:

**
import java.util.Random;
public class Main {
public static void main(String[] args) {
Random random = new Random();
int randomInt = random.nextInt(10) + 1;
System.out.println(randomInt);
}
}
**

This code creates a new Random object and then calls the nextInt() method with a parameter of 10. This generates a random integer between 0 (inclusive) and 10 (exclusive), so the resulting integer can be any value from 0 to 9. To get a random integer between 1 and 10 (inclusive), we add 1 to the result.