Captcha Abbreviation:
Captcha: Completely Automated Public Turing test to tell Computers and Humans Apart.
A CAPTCHA is a security measure commonly used on websites to differentiate between human users and automated bots. It presents users with challenges that require human-like abilities to solve while being difficult for computer programs to crack. The primary purpose of CAPTCHAs is to prevent automated bots from engaging in malicious activities, such as spamming, data scraping, and unauthorized access.
CAPTCHA challenges typically involve distorted or obscured characters, images, puzzles, or logic-based tests that users must solve to prove their human identity. These challenges can include:
1. Image-based CAPTCHA: Users are asked to identify specific objects, animals, or patterns within an image.
2. Text-based CAPTCHA: Users must enter a sequence of characters displayed in a distorted or rotated manner.
3. Audio CAPTCHA: Users listen to a series of spoken characters or numbers and then type what they hear.
4. ReCAPTCHA: An advanced version of CAPTCHA, developed by Google, which uses AI and machine learning to identify human-like behavior. ReCAPTCHA often presents users with simpler challenges, such as ticking a checkbox or identifying objects in images.
CAPTCHAs have become a fundamental part of web security, ensuring that online services and platforms maintain a human-only environment. While they can sometimes be challenging for users, especially those with visual or hearing impairments, CAPTCHA systems continue to evolve to strike a balance between security and user experience.