PHP syntax rules
<p>Im new to PHP, and I am learning about control structures. I just learned about if statements, switch statement and while loops. I know the syntax for an if statement is:</p>

<pre><code>if (condition)
{
    //code to be executed if the condition is true;
}
</code></pre>

<p>switch syntax:</p>

<pre><code>switch (expression)
{
    case 1:
    //code to be executed;
    break;

    case 2:
    //code to be executed;
    break;

    default:
    //code to be executed;
}
</code></pre>

<p>and the syntax for a while loop is:</p>

<pre><code>while (expression)
{
     //code to be executed if the expression is true;
}
</code></pre>

<p>I see the terms condition and argument and expression pretty interchangeably. Do they all mean the same thing? If not what are the differences?</p>
