How to find the length of textarea field and check?

Hi all,
I used one text area field in my form, i want to validate the user input like allowing maximum of 200 words....

Can any one suggest me...

Thanking you...

Here is a really newbie way (that's my level): you can easily set a maximum number of characters by creating a variable:

$limit = 1000;

and then throw an error message if the input on a particular field exceeds that limit:

if (strlen($message) > $limit) {
    $error_msg[]="Your message must not exceed 1000 characters.";
}