Home Blog WordPress Management What is CAPTCHA?

What is CAPTCHA?

What is CAPTCHA?

I have a venerable obsession with efficiency and productivity. I want to do and see many things, but time is, and always will be, an issue. Problems often crop up, threatening to derail the order of things through which efficiency and productivity prosper. Hence, I developed systems to deal with these problems as quickly and as painlessly as possible before they upset the delicate balance. This modus operandi applies to my personal life as it does to my professional life. A prime example of this in my professional life is WordPress activity logging – it is not something I necessarily need every day but allows me to dispatch problems as fast and as efficiently as possible when they arise (because they sure will). Another example is CAPTCHA.

CAPTCHA is way more interesting than the tests we’re now used to may lead us to believe. It has a long and colorful history dating back over 70 years. It has enjoyed many moments in the spotlight throughout this time as it underwent development and refinement to become what it is today.

In this article, we will be going on a CAPTCHA exploration journey, starting at its inception, all the way through the various iterations it went through to become what it is today. We will also be looking at how WordPress websites can leverage what CAPTCHA has to offer to increase WordPress security, reliability, and reputation.

A brief history of CAPTCHA

CAPTCHA has a long and colorful history and has at times courted controversy. Even so, there is no denying that it has been a driving force and major contributor to the fields of security and research alike. Understanding its origins and evolution over time can give us a more profound sense of appreciation for this great technological feat and a better understanding of how we can protect our WordPress websites.

CAPTCHA is an acronym and not a name. It stands for Completely Automated Public Turing test to tell Computers and Humans Apart, and as the name suggests, its job is to tell humans and computers apart.

Following his best friend’s passing, at age 17, Alan Turing started to devote his time to understanding human consciousness. This led him to explore the idea of using math to develop an artificial brain. Twenty-one years later, Alan presented a paper called Computing Machinery and Intelligence, which introduced the Imitation Game – a test to tell humans and computers apart. This was essentially the first CAPTCHA test. The year was 1950.

In the years that followed, many tried to defeat the test through programs that sought to mimic human intelligence through conversation. All of them came up short in one way or another.

Fast-forward to 1997, when the first iteration of CAPTCHA as we know it today was invented. This test involved a distorted image of text and numbers, which a human had to evaluate and decipher. However, it wasn’t until 2003 that the term CAPTCHA was first coined.

Modern-day CAPTCHA

CAPTCHA has come a long way since its inception. It evolved from trying to answer a philosophical question to something we see (and in some cases don’t see) on many of the websites we visit every day.

CAPTCHA comes in different forms and variations. While the original form of distorted text and numbers still exists, we also see more creative and advanced formats. These include clicking on images that show a particular object, such as a bicycle, to a wholly hidden form of CAPTCHA. Instead of an actual test, website visitors are judged on their general behaviors. Let’s take a quick look at how CAPTCHA evolved over the past few years.

The first versions of CAPTCHA were what is known as human-assisted OCR. Tests presented users with scanned tests, which users had to type out correctly in a text box to pass the test. Computers, unable to read the skewed image, could not complete the test and were thus prevented from proceeding forward. This evolved to include pictures, with users asked to identify which pictures showed a specific object, such as a bus or fire hydrant.

Newer versions of CAPTCHA seek to hide the entire process from the user. Instead, it relies on behavioral analytics to determine whether a user is acting like a person or like a computer. This creates a more seamless experience for users without introducing additional steps to sensitive processes such as checkouts.

The different types of CAPTCHA make this tool a truly versatile one that can be adopted and deployed in different situations and scenarios.

The many uses of CAPTCHA

CAPTCHA enjoys great popularity among WordPress administrators for several reasons. While it’s traditionally seen as something to fight off spam with, its benefits extend beyond this.

Reduce spam

The entire premise of CAPTCHA is that it can tell whether a person or a machine is interacting with it. As spam is primarily automated, CAPTCHA can reduce spam on WordPress websites by introducing a test during submission processes. Since spambots cannot pass a CAPTCHA test, the submission never goes through, leaving your website spam-free.

Stop automated attacks

Automated attacks use scripts and other automation technologies to attack websites. Attacks come in various guises and may include:

  • Validation of leaked user accounts
  • Creation of user accounts
  • Account takeovers

With CAPTCHA installed, each of these requires the submission of a valid test, something that automated attacks cannot complete.

How CAPTCHA is used on WordPress websites

As previously mentioned, CAPTCHA is used during input submission, that is to say when WordPress is expecting input from a website user or visitor. WordPress does not support the integration of CAPTCHA straight out of the box. However, thanks to plugins such as CAPTCHA 4WP, securing your WordPress website is fast and easy.

Knowing how and where CAPTCHA is implemented can provide you with valuable insight. In return, this can help you ensure your website is well-protected from spam and other forms of automated malicious acts.

CAPTCHA on WordPress login pages

Login pages are an especially sensitive type of form, which grants users access to resources. Whether it’s contributors accessing wp-admin, customers logging in to WooCommerce, or anything in between, protecting login forms can take on many forms. Enabling two-factor authentication and using strong password policies are more than a good start, with CAPTCHA completing the trifecta of login security.

CAPTCHA stops automated attacks since scripts cannot complete the form submission, giving you more time to focus on what matters to you – such as growing your WordPress website.


WordPress forms come in all shapes and sizes, be it password reset requests, post comments, or anything in between. Forms can be a goldmine for spammers submitting useless links and other junk, which not only looks unprofessional with your users and visitors but can take up a lot of time to clean.

The vast majority of spam is automated, since spammers must rely on volume. CAPTCHA stops such spam right in its tracks, with no action required from your end.

Better spam protection for your WordPress website

CAPTCHA 4WP is our very own CAPTCHA plugin for WordPress that packs a strong punch. It supports multiple ReCAPTCHA versions and features easy integration with WordPress and 3rd party plugins such as WooCommerce, Contact Form 7, and many others.

It’s easy to set up and use and is backed by our world-class support. With over 200,000 installations and multiple plans to choose from, CAPTCHA 4WP is outstanding at helping you stop spam and automated attacks. Get a FREE 7-day trial today to see for yourself how easy it is to get started and stop spam, fake accounts, and fake orders!

Posted inWordPress Management
Mark Grima
Mark Grima

Mark likes to experiment with WordPress and building, or breaking websites with it. Since he is experimenting with WordPress and likes to write he is documenting things that he has learnt, the plugins he uses etc. When not dealing with WordPress sites you'll find Mark in some of the town's best cafes with his friends. You can reach Mark at mark@melapress.com.

Stay in the loop

Subscribe to the Melapress newsletter and receive curated WordPress management and security tips and content.

Newsletter icon
Please enable JavaScript in your browser to complete this form.

It’s free and you can unsubscribe whenever you want. Check our blog for a taste.

Envelope icon