//this method will crash your programm because we sayed "okay lets create a
//int var (x) and read a double in it
public void hello(){
    Scanner sc = new Scanner(System.in);
    int x = sc.nextDouble();
}
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//when you do this:
public void hello() throws Exception{
    Scanner sc = new Scanner(System.in);
    int x = sc.nextDouble();
}

//you programm will not crash because you caught exception, but you dont know where its occured and which exception we have
___________________________________________________________________________________________________________________________
public void hello(){
    Scanner sc = new Scanner(System.in);
    try(
        int x = sc.nextDouble();
     }catch(NumberFormatException e){
        e.printStackTrace();
     }
}

//with this way, we will exactly know where the exption was throws and what exception it was