CAPTCHA is commonly used in web applications' form to ensure that it is nicely filled by humans and not just by any spammers.
There are lots of captcha applications and widgets out there like ReCaptcha. The problem is, this plugin actually used third party server to ensure or to verify the validity of your form. So making it work on an offline and for development purpose is not advisable.
Good thing, a JQuery plugin called Real Person should do the job for you.
This plugin is designed to help overcome automated form submission by requiring a "real person" to identify text made up of dots. The entered value is compared on the server with the generated value by computing a hash to determine whether processing should continue.
What it Does?
Users are forced to identify and provide the text composed of dots. The value that would be provided is compared to a certain hash code on the server side. This will determine whether the said form submission is valid or not.
The said plugin provides lots of useful parameter that can be used to customize it so that it goes with your own form. Some of which are the following:
- Text length can be set
- Can exclude or include numbers
- Can attach image for refresh/regenerate icon