What Are Captchas And How Do They Work?


    The word Captcha is an acronym for ‘Completely Automated Public Turing test to tell Computers and Humans Apart’. A Captcha is a tool that helps the website to figure out who is a human user from a software bot online. The tool is a challenge-response system that asks end-users to perform a task that only a human could carry out. 

    If the person behind the computer is able to do the task correctly then it confirms that they are human and not a software bot with potentially harmful intentions. This being said, there is no way just yet for Captchas to distinguish between harmful bots and the good ones.  

    Here are 6 reasons why companies use Captchas for security:

    • Bots are known to interfere with important online polls by sending repeated responses to benefit a business or individual. Captchas assist in keeping these untrustworthy bots at bay.
    • If hackers are really wanting to get into an account, they will repeatedly try to log in using hundreds of different passwords. Captchas help to stop this process in its tracks before any damage has been done.
    • To prevent hackers from signing up for multiple email accounts that they’ll then go on to use for their sneaky scamming intentions.
    • To ensure hackers can’t get access to blogs or news content pages where they could leave comments or links that would alienate the audience or clientele.
    • To regulate people who use bots to buy huge amounts of tickets for shows, concerts or gigs to benefit them financially.
    • To  secure online shopping experiences

    Different Kinds Of Captchas

    There are varying types of Captchas, but the 2 most common types are as follows:

    1. Text: The most common type of Captcha is the text Captcha. It asks the user to view distorted letters or distorted text, usually containing a string of alphanumeric characters in an image, and then to type the letters or numbers in the box below the image.

      2. Picture Recognition: The other type of most commonly used Captcha is when the Captcha asks the user to identify a bunch of images within a larger set of images. For example, the user may be given a set of pictures and asked to click on all the ones with cars, buses or street signs.

    The Best Ways To Deal With Captchas

    We can use an OCR (Optical Character Recognition) approach for the text-based Captchas, providing they are simple enough. There are OCR engines like Google Cloud or Microsoft Cloud OCR, or you can also use Python code with purpose-built libraries that use OCR and Machine Learning to recognize the text in the image.

    Some Captchas are a bit more complicated, for those the most user friendly thing to do is outsource your needs to a third party Captcha solver service. These are able to address and solve many different types of Captchas.

    Captchas were created to protect sites that offer online blackjack real money and other activities, companies and businesses from any dodgy activity caused by malicious programmes or bots. Captchas are continuously evolving to protect against different levels of online threat.



    Please enter your comment!
    Please enter your name here