I cannot figure it out why the `for loop` is created in spite of having `while loop`.
In my opinion, they are the same even through someone says that the `while loop` is used when we do not know an iteration number. In that case, we can also use `for loop`, can't we?

For example,

**For loop:**

```
for (;true;)
{
    document.write("Hello World <br>");
    if(somecondition){
       break;
    }
}

```

**While loop:**

```
while (true)
{
    document.write("Hello World <br>");
    if(somecondition){
       break;
    }
}

```

Moreover, the complexity of the two kinds of loops are the equal. So, why the loops do not be deleted and rest only one kind?