The What And Why Of ‘Captchas’
Posted: March 5, 2013
Double Clicks
I often field questions about the letters used as a security measure on websites. These are known as “captchas,” a term based on the word “capture.”
When captchas first became popular, they typically required that one word be retyped into a text box in order to proceed to a site’s next step. I use “word” loosely since captchas were typically a combination of letters, usually not spelling an actual word.
Today, captchas have advanced to multiple words or letter/number combos, such as “ck1U8iuX7,” and often appear slanted or wavy.
At first, it was easy but, with the addition of numbers, capitalizations and slants, letters and numbers became more difficult to distinguish.
Was that a numeral one or the lowercase letter “l”? Is that a twisted capital “X” or lowercase? If you’re not sure, a reload button — the icon is one curved arrow directing another — was added. If you click that button, another word should appear.
Later, site designers added an option to “speak” the word. The icon is usually represented by a small speaker.
OK, now that you understand what captchas are, you may still be wondering why they are necessary.
Captchas were created to keep Internet robots — sometimes called “net-bots” — from signing up for accounts on websites. For example, if I’d written a book, and decided to offer the first 100 people who joined my website a free copy, a net-bot could register hundreds of fake users in a matter of seconds.
The captcha process is called a “challenge-response test,” which means that, in order to ensure you are a real human, it gives tests computers cannot pass.
The “challenge” is deciphering the words in the graphic box, the “response” is reentering the pattern into a text box.
If you pass the test, you advance to the next step; if not, you can battle another captcha until the test is passed.
I use a captcha program called, “reCAPTCHA,” owned by Google. The company claims they display more than 100 million captchas every day through the service.
Captchas are a pain, but it is all about Internet security. Embrace it.
See if you can pass the test, visit DoubleClicks.info and click the “Contact Ron” link in the upper left corner of the page under “Pages.”
If you’re looking for a laugh, click the speaker to hear the hint.
When captchas first became popular, they typically required that one word be retyped into a text box in order to proceed to a site’s next step. I use “word” loosely since captchas were typically a combination of letters, usually not spelling an actual word.
Today, captchas have advanced to multiple words or letter/number combos, such as “ck1U8iuX7,” and often appear slanted or wavy.
At first, it was easy but, with the addition of numbers, capitalizations and slants, letters and numbers became more difficult to distinguish.
Was that a numeral one or the lowercase letter “l”? Is that a twisted capital “X” or lowercase? If you’re not sure, a reload button — the icon is one curved arrow directing another — was added. If you click that button, another word should appear.
Later, site designers added an option to “speak” the word. The icon is usually represented by a small speaker.
OK, now that you understand what captchas are, you may still be wondering why they are necessary.
Captchas were created to keep Internet robots — sometimes called “net-bots” — from signing up for accounts on websites. For example, if I’d written a book, and decided to offer the first 100 people who joined my website a free copy, a net-bot could register hundreds of fake users in a matter of seconds.
The captcha process is called a “challenge-response test,” which means that, in order to ensure you are a real human, it gives tests computers cannot pass.
The “challenge” is deciphering the words in the graphic box, the “response” is reentering the pattern into a text box.
If you pass the test, you advance to the next step; if not, you can battle another captcha until the test is passed.
I use a captcha program called, “reCAPTCHA,” owned by Google. The company claims they display more than 100 million captchas every day through the service.
Captchas are a pain, but it is all about Internet security. Embrace it.
See if you can pass the test, visit DoubleClicks.info and click the “Contact Ron” link in the upper left corner of the page under “Pages.”
If you’re looking for a laugh, click the speaker to hear the hint.
Contact Ron Doyle at ron@doubleclicks.info.