CAPTCHA Explained

Howard Lerner

Howard Lerner

CAPTCHA Explained

CAPTCHA Explained

CAPTCHA Explained

three captcha versions
These puzzles prevent spam

You probably know CAPTCHA as those puzzles you face when completing a web form or submitting a comment.

CAPTCHA – and its newer version, ReCAPTCHA – limit annoying or harmful comment spam generated by robot (bot) activity.

Because bots can’t solve (or even see) the puzzles, CAPTCHA won’t allow the incomplete form to be submitted, eliminating the spam before it enters the website database.

First Generation CAPTCHA: A problem only a real human can solve

The technology works because only real humans can identify the blurry or squiggly challenge words, eliminating bot comment submissions.

CAPTCHA is great for spam reduction, but frustrating for users.

The problem is however, many real humans can’t solve the computer-generated CAPTCHA challenges, leading to frustration and lower user conversion rates.

Next came Google’s “ReCAPTCHA” which is less frustrating for users.

ReCAPTCHA as a crowd-sourced technology solution

For years, Google has been scanning millions of books, creating the world’s largest digitized library. Those scans, however, often yield words that even Google’s sophisticated optical character recognition (OCR) software can’t understand.

ReCAPTCHA V1 was a more user-friendly approach to limiting comment and form spam

In an effort to decipher these words, Google inserted them into it’s new CAPTCHA challenges, and named it “ReCAPTCHA V1.” If enough real people copied the letters in the same manner, Google had its answer, saving employees from performing the tedious task. Brilliant, huh?

Google expands the ReCAPTCHA mission to keep streets safe

Google uses complex software to identify street features such as bridges, lights and crosswalks. Mistakes in identification, however, can cause problems as Google advances its automated car technology.

When you identify a bridge, crosswalk or a traffic signal in a CAPTCHA V2 challenge, you’re not just fighting spam, you’re helping Google generate more reliable street maps. Super brilliant!

Google doesn’t need our ReCAPTCHA help anymore

captcha traffic lights2
ReCAPTCHA V2 crowd-sources problems the Google Maps algorithm can’t solve while fighting comment spam

When you check a box to “prove you’re a human,” That’s ReCAPTCHA V3, which is a significant user experience improvement.

With ReCAPTCHA V3, The bots can’t see the question and the user doesn’t have to solve puzzles to submit a form.

Recently, Google stopped crowd sourcing its identification problems. Because its character recognition and traffic feature identification have improved so much, Google doesn’t need our help anymore.

ReCAPTCHA V3 takes the problem-solving challenge out of the bot-fighting process

Invisible ReCAPTCHA makes a better user experience

The latest standard in comment-spam reduction is “Invisible ReCAPTCHA.” It’s invisible because Google uses its anti-spam algorithm to identify the quality of the visitor, rather than force the visitor to prove their humanity.

ReCAPTCHA scores the visitor on a number of factors. But when that score falls short, the user is presented a problem only a huma can solve.

While Google doesn’t explain which factors it uses to identify a bot, the technology appears to work well. But DecemberPress has tested Invisible ReCAPTCHA and have not detected any “false negatives.”

Invisible ReCaptcha logo
Invisible ReCAPTCHA works in the background, fighting comment spam

You know that Invisible ReCAPTCHA is at work when you see the ReCAPTCHA logo at the bottom right of a web page.

DecemberPress uses Invisible ReCAPTCHA uses Invisible ReCAPTCHA to fight comment and message spam. The tool has significantly reduced comment spam from about 20 incidents day to about one every three days.

Sadly, some spam messages are inevitable because there are spammers who employ low-wage, real humans to troll about the internet and manually complete forms, inserting spammy or malicious links into web forms.

For a deeper understanding, visit the official CAPTCHA and Re-CAPTCHA sites or check out this short video.

If you’re experiencing annoying comment spam, contact DecemberPress for the right solution.

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DecemberPress is a St. Louis, Missouri-based full-service digital marketing agency offering web design, content strategy, and pay-per-click services. We offer web hosting and maintenance for small business and startups.


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