What is CAPTCHA?
A CAPTCHA is a type of challenge-response test used in computing to determine whether or not the user is human. CAPTCHAs are used for a variety of purposes, such as preventing automated software from being able to access certain websites or services.
There are a variety of different CAPTCHA types, but the most common is the text-based CAPTCHA. These CAPTCHAs require the user to type a series of letters and/or numbers that are displayed in an image. This type of CAPTCHA is designed to be difficult for robots to read, but easy for humans.
Another common type of CAPTCHA is the audio CAPTCHA. These CAPTCHAs provide an audio recording of a series of letters and/or numbers that the user must then type into a form. Audio CAPTCHAs are designed to be accessible to users who are visually impaired.
CAPTCHAs are not perfect, and they can sometimes be difficult for humans to read as well. However, they are still an effective way to prevent automated software from accessing certain websites or services.