Some CAPTCHAs can be very hard to read, even for people with good vision. Basically, the intention of a CAPTCHA is to prevent spam from robots but they also cause inconvenience to real users especially blind and visually impaired people. There are various types of CAPTCHA including typing in the shown words or numbers, doing some simple maths, solving a visual puzzle, identifying objects, and etc. Understanding the methods that spammers use to circumvent CAPTCHA sheds light on why those CAPTCHA codes can be hard to enter.If you’ve submitted a form or registered for an account on the Internet, you will have stumbled upon a CAPTCHA. However, there's a good reason why they are not easier.īlocking cheaters and spammers is a game of cat and mouse Cheaters are always trying to crack CAPTCHAs and companies are always trying to strengthen their security to make them harder to get around while letting legitimate entries through. They might also ask you to perform other actions, such as picking all of the pictures that show a house or a road sign.Īlthough they're supposed to be easy for humans to solve, CAPTCHA codes can be confusing frustrating. Some CAPTCHAs offer the option to listen to the letters as they are spoken out loud, which is especially important for the visually impaired. This is also a test that is difficult for a computer to pass. Instead of strange letters and numbers, some CAPTCHAs ask people to play a game, such as putting all of the moving images of food on a plate while ignoring images that don't show food. Software programs cannot easily identify the letters and numbers by their shape. To make it difficult for computers to read the characters, CAPTCHAs are often distorted or placed on a confusing background pattern. In theory, computers can recognize text from images - but to do so reliably, they need a clean, crisp image. The entrant needs to type those characters before they can submit the form. The most common CAPTCHAs display a series of letters and numbers. They also prevent fraudulent sweepstakes entries and illegitimate votes in contests. They prevent hackers from performing 'brute force' attacks where they try to break into an account by guessing every possible password combination. What's behind the funny name? CAPTCHA is an acronym that stands for 'Completely Automated Public Turing Test to tell Computers and Humans Apart.' A Turing Test is a test for intelligence in a computer or a program.ĬAPTCHAs have a wide range of applications. It's intended to prevent bots, automatic sweepstakes entry services, hackers, and similar automatic logins from cheating the system. A CAPTCHA is a test that checks whether a human, not a computer program, is submitting an online form.

Solving captcha