Hi,
Search engines do not index some common words (such as “or”, “and”, “when”, and “in”) within the webpage. What are these common words called?
Nice method, although you should sanitise the user’s post data like so:
In your contact form add an input field:
What color is the sky?
Answer: <input type="text" name="ans" />
Then, in the php file that gets data form, add:
//simple captcha
$_POST['ans'] = mysql_real_escape_string(strip_tags($_POST['ans'])); //clean post data
if(isset($_POST['ans']) && $_POST['ans']!='blue') exit('Wrong answer');
//simple captcha