In this article we will learn how to use Google's new Recaptcha "I am not a robot" in asp .net with code behind implementation. You can also download attached sample code. reCaptcha is a free service offered by google which helps to fight against bots and spams.  Google has launched a new version of reCaptcha which is very secure and good looking from previous versions.

In this article we will learn how to use google's reCaptcha by adding reCaptcha DLL and by using Nuget package in asp .net. CAPTCHA is abbriviated as "Completely Automated Public Turing test to tell Computers and Humans Apart" it is a test to distinguish between human and automatic bots. 

In this asp .net tutorial we will learn how to create custom mathematical numeric CAPTCHA with arithmetic operations inside our comment module. This numeric CAPTCHA will generate two random integer numbers and users have to add those numbers to solve the CAPTCHA. ThisCAPTCHA will helps us to stopping spam comments in our website.

  In this Asp .Net tutorial we will learn how to create custom image CAPTCHA . Captcha is used to determine whether the user is human or bot. Captcha's are really very  useful to stop spams and invalid data insertion by BOTS.