editing readme file

Author: phpcodertop

README.md

@@ -1 +1,13 @@
-# phpcaptcha
+# php captcha class for security check for human usage 
+# Usage : 
+# Your Captcha image src should point to captcha.php
+
+# Check :
+# compare your user input with $_SESSION['secret']
+
+# Example check
+if(!empty($_POST['input']) && $_POST['input'] == $_SESSION['secret']){
+			echo 'good';
+		}else{
+			echo 'wrong';
+		}