Question

What is the difference between:

Ex 1.

<script type="text/javascript">   
document.write("<h1>This is a heading</h1>");   
document.write("<p>This is a paragraph.</p>");   
document.write("<p>This is another paragraph.</p>");   
</script>  

Ex 2.

<script type="text/javascript">   
{   
    document.write("<h1>This is a heading</h1>");   
    document.write("<p>This is a paragraph.</p>");   
    document.write("<p>This is another paragraph.</p>");   
}   
</script>

W3C Schools says:

Ex 1. Each statement is executed by
the browser in the sequence they are
written.
Ex 2. The purpose of a
block is to make the sequence of
statements execute together.

Please explain the above statements. How does the browser acts differently upon the above commands?

Answer 1

No difference at all, the purpose of a block is to be used in ifs and fors, like so:

Ex 1
if ()
//command to execute

Ex 2
if ()
{
// many commands to execute
}

In the second sample, the if statement “sees” the block command as a single command, inside the block, the commands still are executed in order.