import java.util.concurrent.TimeUnit;
public class T01_whatIsThread{
private static class T1 extends Thread {
    @Override
    public void run(){
        for (int i = 0;i<10;i++){
            try {
                TimeUnit.MICROSECONDS.sleep(1);
            } catch(InterruptedException e){
                 e.printStackTrace();  
            } 
            System.out.println("T1");
            }
        }
    }
    
    public static void main (String[] args) {
        // new T1().run();
        new T1().start();
        for(int i=0;i<10;i++){
            try {
                TimeUnit.MICROSECONDS.sleep(1);
            } catch(InterruptedException e) {
                e.printStackTrace();
            } 
            System.out.println("main");
        }
    }
}