What is captcha and How it work [कॅप्टचा क्या है और ये क्या काम करता है]

        Hi Guys, In entire life you ever visit any website or create an account on Google, then you will definitely see such a captcha code so many times.

Image Source - google | Image by - WikiHow.com

        But have you know that What is this CAPTCHA? After all, why is it shown to us? Is this question bothering you too, so let's learn in this Article.

Hey Guys my name is DIPAK and let's get start it 

What is Captcha :-

Before knowing CAPTCHA, let's understand it with small example.

        Suppose if I have go out for some urgent work by train so what will I do? I will go to IRCTS (Indian Railway Catering and Tourism Corporation) website and Simpley Book a tatkal tickit (तत्काल तिकीट).

        If  I have to book a tatkal ticket. what will I do,  firstly open the pc or laptop go to the website Login and select the train, fill up all the details and make payment.

        So all of this process will take a minimum of 2-3 minutes, but if  any programmer make a script or program which can Execute this work, that mean's work will automatically done by this script, So he doesn't have to do any thing. He just need to write a command like which work to do and at what time.

        So The script automitacly login to the website, select the train, fill up the details automatically and make payment.

It means the work that took me 2-3 minutes to do, it will be automatically done in just 10 seconds with the help of bots or machine

So the biggest problem for the whole world is,

• how to find that whether the inpute given to computer is given by human or any machine.

        because If a programmer writes the script in this way, The result is lakhs of train books in few seconds and millions of forms will be filled in 1 second, The Tatkal ticket will end as soon as it open people will not be able to get it. 

That's why the concept of Captcha brought

What is Captcha:- 

            a computer program or system intended to distinguish human from machine input, typically as a way of thwarting spam and automated extraction of data from websites.

Full form of Captcha:-

C = Completely

A = Automated

p = Public

T = Turing test to tell 

C = Computers and

H = Human

A = Apart

 Types of Captcha (Captcha Example) 

  1. TEXT CAPTCHA

In this type of Captcha you have to solve by typing Alphabet above.

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2. AUDIO CAPTCHA

You will hear an audio in Audio Captcha. You will have to type that audio by typing it.

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3. IMAGE CAPTCHA

                                                                             Credit-Auth0

This type of captcha shows you the captcha image, from which you are asked to choose one of the images.

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4. MATH SOLVING CAPTCHA

In this captcha you have to add or subtract some numbers.

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      5. 3D CAPTCHA

In this type of Captcha, you are shown the image in 3d.

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6. AD INJECTED CAPTCHA

In this type of Captcha, you see the code through Ad. The name of the Ad you see on the screen has to be filled only. It can also have the name of a brand. 

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       7. Jquery SLIDER CAPTCHA

This is a plugin that gives Ability to add Captcha. It is also easy to use, this plugin is very useful in keeping the spammer away.

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       8. TIK TAC TOE CAPTCHA

This Captcha contains some Gamifications Involve. Which is designed as Fun. This is a very easy way for Humans to interact with the website.

WHAT IS RECAPTCHA:-

            reCAPTCHA is a free service from Google that helps protect websites from spam and abuse. A “CAPTCHA” is a turing test to tell human and bots apart. It is easy for humans to solve, but hard for “bots” and other malicious software to figure out. By adding reCAPTCHA to a site, you can block automated software while helping your welcome users to enter with ease. 

Demo Captcha Link:- https://www.google.com/recaptcha/api2/demo

! THANK YOU !