This library can help you create a captcha in your terminal application, which may be damaged by a large influx of requests.

0-9 arası sayıları kullanarak random olarak 2 sayı seçer ve yine random olarak toplama ya da çarpma yaparak sonucu verir.

A simple and custom captcha for Rails3.

Google reCaptcha helpers and verifier

anti-captcha is a Ruby library for recognize captcha on anti-captcha.com

Implements view helpers for the ASIRRA CAPTCHA system for Rails-based websites

Integrate the AreYouAHuman.com CAPTCHA alternative human verification into your Ruby/Rails application

you will get arithmatic sum with answer you just have to compare with ur user in controller

Captcha based on encyrpting and decrypting user data by mathematical operation

Submit captcha images and retrieve the text as a string.

Captchator as Rack middleware, and helpers for sinatra.

RedisCaptcha provides simple captcha that can be read by human.

Rails mountable engine, that provides captcha support

Simple negative captcha for Rails

Implementation of captcha (Completely Automated Public Turing-Test to Tell Computers and Humans Apart) that is both easy to use and easy to customize/extend.

Description of TinyCaptcha.

Simple, easy captcha for Sinatra

Solve Media CAPTCHA Replacement

Simple captcha based on plain text questions.

Captcha generator for rails