I can't solve this problem

[Atanu]

<?php
$a=5;
$b='a';
echo $$b;//it prints 5.
?>
I know it's a dynamic variable.But why it is called DYNAMIC?what is the exact defination of DYNAMIC?????
please reply.please.

[Zane]

it means that it could change any time you want it to......


for instance if you had a loop like this
[code=php:0]
for($i=0; $i<3; $i++) {
    $b='i';
    echo $$b;
}[/code]
it would print
012


http://en.wikipedia.org/wiki/Dynamic_programming

[kenrbnsn]

In PHP this is a [url=http://www.php.net/manual/en/language.variables.variable.php]variable variable[/url].

Ken

[Atanu]

When will we use it?