To get your <form> result sent as an array to your PHP script you name the <input>, <select> or <textarea> elements like this:
<input name="MyArray[]" />
<input name="MyArray[]" />
<input name="MyArray[]" />
<input name="MyArray[]" />
It’s also possible to assign specific keys to your arrays:
<input name="AnotherArray[]" />
<input name="AnotherArray[]" />
<input name="AnotherArray[email]" />
<input name="AnotherArray[phone]" />
he AnotherArray array will now contain the keys 0, 1, email and phone.
[http://us3.php.net/manual/en/faq.html.php#faq.html.arrays]