Meaning of CAPTCHA

Completely Automated Public Turing Test To Tell Computers and Humans Apart is the elaborated form for CAPTCHA.  Internet users often come across a CAPTCHA test at some point. It is a tool designed to identify whether an internet user is a human or a bot. Although CAPTCHAs are planned for blocking programmed bots, they too are automated. There are different types of CAPTCHA to validate incoming users on websites. For example, image or pattern recognition, identifying words or numbers, etc.

Background of CAPTCHA:

The part of CAPTCHA Stands for Turing Test, named after its inventor Alan Turing. Also, known as the father of modern computers, Turning designed CAPTCHA to trick machines. Over the years, bots or spam visitors access websites to increase the visitor count, hence CAPTCHA is a viable tool to tackle the issue. The algorithm used to design different types of CAPTCHA was capable enough to stop malicious activities from visiting the website. Also, distinguish computers and humans without any human intervention. Therefore, several website owners have accepted the idea of the CAPTCHA test to guard websites.


Uses of CAPTCHA:

The utilization of CAPTCHAs is required for online applications which require client input. Explicit utilization of it is to limit bots to decrease spam and increase the number of legitimate users. This challenge-response system is a security test to prevent spammers and hackers from inserting frivolous code online into websites. Some of the uses of CAPTCHA are the following:

  • One of the uses of CAPTCHA is to maintain poll accuracy ensuring that humans have entered votes.
  • Restricting multiple account creation prevents waste of resources and fraud. Hence, the uses of Captcha limit the registration of services.
  • Among various uses of CAPTCHA, one is to prevent the purchase of large numbers of resale tickets. It also forestalls bogus enlistments to free occasions. Therefore, avoiding ticket inflation at excessive prices.
  • Websites encounter spammed messages. The uses of Captcha restrict inappropriate comments and auto-replies. Thus, allowing only human beings to post comments and helping your page to grow organically.
  • Another one of the uses of Captcha also prevents hackers from attempting to log into an email account unethically.
  •  Other uses of Captcha include fraud prevention while making online shopping. Competitors may use bots with invalid names, emails, and shipping addresses to order products. Thus, fitting captcha on eCommerce websites gives surety to buyers being humans.

 Understanding ReCAPTCHA

ReCAPTCHA is the advanced version of the CAPTCHA system that uses advanced risk analysis techniques to protect websites from spam and abuse. CAPTCHA allows users to access websites based on their responses to the different types of captcha tests like image-based, word-based, number problems, audio-based etc. Whereas the re-captcha system allows access to websites based on your activity. Since reCAPTCHA is less time-consuming as it doesn’t involve time to answer questions to identify what is not a bot. Therefore, it has wide acceptance among website users.


Popular Types of Captcha:

CAPTCHA has been part of your daily experience on the internet that verifies users. Also, prevents automated programs from accessing your websites and data. There are several ways to configure CAPTCHA to protect websites.

Math Problems type of Captcha:

Types of Captcha- Math Problems
Math Problem Captcha

This is one of the most popular types of CAPTCHA. Math problems CAPTCHA have simple mathematical questions to solve and enter the answer. The accuracy of the user’s response decides the status of access. However, this test doesn’t guarantee the security of a website because it is not complicated as other types of captcha.

Word Problems types of Captcha:

Text based type of Captcha
Text based Captcha

This is one of the popular types of captcha. A word problem asks you to type the missing word in a sentence. It is important to follow the directions carefully as it might ask you to retype the wrong sequence of letters, enter the first word or identify the colour of displayed words. This sort of test often has the option of audio-based CAPTCHA for visually challenged users. Word problems CAPTCHA is often considered secure by website hosts since it requires logical understanding to comprehend.

Image-based types of Captcha:

Image type Captcha
Image Based Captcha

This is easy for humans to interpret in comparison to text-based CAPTCHA. It has different kinds of image tests like an odd picture out, naming the image, recognizing the image, etc. These tools have discreet availability issues for visually impaired users. However, such Captcha is difficult for bots to interpret as it has both image recognition and semantic classification.

Honeypot types of Captcha:

Types of Captcha-Honey Pot
Honey Pot Captcha

It is one of the most difficult types of captcha. In this type of captcha, the user helps to find the hidden items on the screen. types to exist currently. The advantage of the Honey pot captcha is that it doesn’t involve inputting much information or complicated games. Hence, saves time for genuine users on the websites. However, there is the possibility of smart bots easily detecting the trick with no effort, therefore deceiving the algorithm behind the captcha.

Time-based types of Captcha:

Types of Captcha-Time Based
Time Based Captcha

This test records the amount of time a user spends completing the form. Bots tend to fill out the form immediately while humans take time to enter the required information. However, some users may get disappointed when they fail to meet the time limit of the captcha. Also, becomes time-consuming to refill the form.

Audio types of Captcha:

Technique to identify visually impaired humans
Audio Captcha

This is created specifically for visually impaired users, thus addressing the availability of the website for all users. Audio Captcha is a combination of image-based and text captcha. It plays audio, which the user inputs. Bots are unable to identify the significant characters from background noise but are sometimes challenging for humans too to decipher.

Confident types of Captcha:

How to protect your websites?
Confident Captcha

This is one of the most common types of Captcha. It is an image-based method to find matching items based on questions. For example, to find traffic lights or cars in a grid. The pictures can be static or dynamic. Confident captchas have a high success rate as it is user-friendly tests. However, if not performed correctly the first time then retrying with multiple images is time-consuming.

No Captcha:

No Captcha
No Captcha

This is the easiest type of captcha for users in comparison to other types of captcha. In this test, you just have to select a checkbox confirming that you are not a robot. It is effective and precise as it tracks the user’s movement and clicks to distinguish between human activity and a bot. For this reason, humans can easily complete this test with no effort but difficult for bots. However, if the user is identified as suspicious, an image captcha box appears and the user must have to pass the test.

Invisible types of Captcha:

Invisible ReCaptcha
Invisible ReCaptcha

This is a unique type of captcha as it doesn’t require any user input. It is an updated version of No Captcha. These captchas are developed by google using an advanced version of pattern recognition. Instead of testing directly, they analyse the way you use the website like mouse movements, typing style, etc. to know if a user is a human is a bot. An Invisible captcha aims to make more satisfying customer experiences without any user interaction.


Social Media Sign-In:

Sign In through Social Media- ReCaptcha
Social Media Captcha

This is a popular alternative to CAPTCHA, where users can use social media profiles such as Facebook, Google or LinkedIn to sign up. This type of captcha saves time for users and increases the security of the website from bots since they don’t have any direct connection with social media accounts. Despite all these, this still can be disruptive to link a new website to your social media account i.e. intrusion into your personal information.

Sweet types of Captcha:

Sweet Captcha Example
Sweet Captcha

In this type of captcha, you need to match sweet types of images instead of solving complicated digits and characters. It is an effective instrument but sometimes difficult to speculate. Thus, Sweet captcha is difficult for bots to crack but at the same time, may not give a user-friendly experience to genuine users too.

Biometric types of Captcha:

Biometric Face Recognition-Captcha Type
Biometric-Face Recognition

This is a next-generation captcha that uses sensors for finger impressions instead of filling in the user’s name and password. Unique fingerprints of each user prevent bots from spamming the websites unless sabotaged. The only challenge could be that you cannot reset the account as biometric responses on a physiological level like facial, speech or finger recognition, etc.

3D Captcha

Examples of Captcha- 3D Captcha
3D Captcha

This is a next-generation type of Captcha employed for human authentication. Also, better familiar as the Completely Automated Public Turing test.


Ad-Injected Captcha

Examples of Captcha- Ad Injected Captcha
AD Captcha

 These types of Captcha make sense in terms of brand recognition and awareness. The captcha images display ads not only to earn some extra money but also to associate themselves with brands.


Tic Tac Toe Captcha

Captcha and its examples - Tic Tac Toe Captcha
Tic Tac Toe Captcha

 These are well-designed types of Captcha which will be fun and easy. The website visitors are presented with a quick game by moving 3x in a row.


How does CAPTCHA work to prevent scammers?

The functioning of Captcha is to analyse the difference between human and automated computer programs. The different types of Captcha rely on the human ability to think and recognize unique patterns. On the other hand, bots follow a set of programmed patterns. Unlike humans, bots find it difficult to recognize images or pictures from different patterns and shapes. Also, segmenting a character from distorted or overlapped words or numbers is not easy for bots to interpret. For this reason, captchas were created to throw challenges that limit the bots to deal with but are easy for humans to respond to.

Since the introduction of CAPTCHA, bots are also evolving using artificial intelligence to decipher Captcha and spam websites. Therefore, several new methods are devised for maintaining the security of websites. One such newer version of Captcha created is known as ReCAPTCHA. The idea behind ReCAPTCHA is to understand the fact that humans are smarter than programmed patterns. Thus, growth in technology has created an urge to develop novel captcha tests to figure out human clients from bots.

How do spammers defeat CAPTCHAs?

Skilled cybercriminals and hackers are able to bypass a CAPTCHA. Most of these hackers use artificial intelligence tools to define algorithms that can predict captcha patterns.  Another way is to pre-install large numbers of captchas and learn to decode them. So, it is highly recommended to adopt adequate security measures and keep protected the users’ data.

How can you keep CAPTCHA codes secured?

The website is protected as long as CAPTCHA is secured. You can join Henry Harvin’s cyber security course to learn techniques to keep the captcha code secured. The most viable ways to secure CAPTCHA codes are the following:

  • The image should be randomly distorted before it is presented to the user of a website.  This way it can work as a shield against automated attacks.
  • ‍Deploying matchless CAPTCHAs for all the websites defeat hackers who predict algorithms of the same sort of patterns. Changing the captcha, creating unique codes and not following the same patterns decrease the predictability of bots hacking the websites.
  • ‍Using uncommon equations gives a tough time to hackers bypass different types of Captcha. Thus, it is better to have no captcha rather than to have common captchas.
  • Images should be non-readable for computer programs. So, open-source Captcha scripts should be avoided.
  • ‍Combining one or more types of Captcha makes it more complex and secure. For example, you can combine a text-based captcha with an image captcha to protect your website.
  • ‍Antivirus software helps in securing CAPTCHA codes to keep malicious content away.

Benefits of Captcha:

The impressive advantages of Captchas working on your websites are the following:

  • Highly effective against most bots. Thus, discouraging unwanted access to your websites.
  • The uses of Captcha improve the accessibility to a website easily by stopping fake and ill-intended usage.
  • Prevents ruining your website from a good user experience by securing user login and passwords.
  • Provides genuine users to wade through comments sections rather than filled with automated responses.


Challenges of Captcha:

Though the uses of captcha are ideal options, still there are significant disadvantages too. Creating a balance between security with accessibility is not often easy. Therefore, making it exponentially harder. Although, these can be improved upon in the coming time.

  • Solving CAPTCHA needs time and effort so can be sometimes frustrating for users.
  • Indeed, it is an effective tool against spammers but still has partial benefits methods for your website. Sometimes, bots can fool these tests with machine learning capabilities.
  • Complicated captchas can be disruptive for some users. So, they might drop the idea of visiting the website. Hence, may lead to a drop in website traffic.
  • Some visitors might find it challenging to understand and comprehend Captcha. Therefore, the uses of captcha are only feasible for some audiences.
  • Some types of captchas do not support all browsers so might affect lead generation if the sole purpose of the site is to drive traffic.
  • Visually impaired users find it impossible to access all important sites due to the presence of a captcha unless you have placed an audio captcha. So, you won’t be able to target such users who are also part of society.
  • If your site is accessible to people who are comfortable in languages other than English then it could be a struggle for such website visitors. They might need time to understand the language and then interpret the captcha code.

Functioning of Captcha:

A Turing test assesses a machine’s ability to imitate human behaviour. The functioning of Captcha is created on the Turing test. It is named after its inventor Alan Turing.  A Turing test is not about tracking the right course of action but suitable human reactions. The functioning of a captcha is built on common sense and replying capabilities to differentiate between bots and humans. To accomplish this, it needs to allot a simple that users can perform while computer programs struggle. Usually, humans have a high percentage to pass Captcha tests. But with the development of bot attack strategies, it attempts to spam the websites and thus fail the captcha tests. However, the technology giants are working on advanced functioning of captcha to gain organic development on a website page.

Role of Artificial Intelligence in creating Captcha and ReCAPTCHA:

Generally, computer programs find challenging to identify objects and texts. Whenever a user solves a captcha, the data is fed into an artificial intelligence machine. Further, it helps in distinguishing differences between images like crosswalks, trains, trucks, etc. The program should have enough data to build effective AI programs. For this reason, ReCAPTCHA fulfils the needs of humans to identify objects, texts or both. Hence, artificial intelligence programs help in overcoming all limitations of identifying different types of Captcha.

So, reading this blog, you must have realised the increasing uses of captcha. So, if you plan to make a career in Cyber Security, it covers developing different types of Captcha as a part of the curriculum. You can join Henry Harvin’s cyber security course. It is a program that allows learners to practice in a real-time simulated environment. Thus, giving them an edge in this competitive world.

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Sometimes, the intention is to damage your website or extract users’ information using unfair practices for different reasons. Functioning of a captcha is to protect a website from illegitimate website visitors. There are various types of captcha available like text-based, math problems, audio-based, and many more. While Captcha sounds like an ideal solution but still not suggestive. This is because there is a scope for improvement, the challenges it has. To conclude, the uses of Captcha are growing exponentially to be a complete security option for website owners.

Frequently Asked Questions

Q1. Which types of Captcha are best for your Website?

Captcha plays an important role in identifying real humans. Every captcha has its advantages and challenges. You can decide according to your requirements for the security of the website.

Q2. Are the uses of Captcha an ideal solution for protecting your website?

There are some disadvantages to using Captchas as some of them may not be compatible to block the bots.

Q3. When was the first Captcha developed?

The first CAPTCHA was created in 2000 at Carnegie Mellon University to prevent automated programs from signing in multiple accounts.

Q4. How does the functioning of CAPTCHA perform?

Captchas can filter spammers and identify humans. Thus, protects your website’s usability and accessibility.

Q5. Are there any alternatives to different uses of CAPTCHA or reCAPTCHA?

Many bot management solutions can identify bad bots. Hence, mitigating the risk without forcing users to complete inputting captchas.

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