When filling out online forms, it’s likely you’ve used CAPTCHA. You know the wavy words and letters at the bottom of the form that you must interpret to prove you’re human? That’s CAPTCHA. (Developed at Carnegie Mellon University, the acronym stands for “Completely Automated Public Turing test to tell Computers and Humans Apart”, by the way.) Until recently, this wasn’t something that average developers could easily take advantage of. But then came reCAPTCHA to forms.
A reCAPTCHA form is one that protects you from comment spam or bogus registrations using a free widget that you can implement using PHP, a WordPress plugin or other pre-coded method. As they say on their website:
…adopting it is as simple as adding a few lines of code on your site. For many applications and programming languages such as WordPress and PHP we also have easy-to-install plugins available. We generate and check the distorted images, so you don’t need to run costly image generation programs.
Here’s an sample of what reCAPTCHA looks like when implemented into a web form:

What’s great is that it serves its purpose but does so while maintaining disabled accessibility through its audio test option.
But there’s a wider purpose for reCAPTCHA… their wavy words actually come from books that need human intervention to digitize. Instead of hiring hundreds of data entry personnel to convert old books and newspapers to digital, they use their service and the Internet community as their labor pool. Ingenious! It’s no wonder Google recently purchased the company.
- reCAPTCHA WordPress Plugin
- reCAPTCHA PHP library
- reCAPTCHA API (for advanced development)
- MarketingPilgrim post about the acquisition
- Spanish translation of this article – Forma de reCAPTCHA
