What is CAPTCHA?
CAPTCHA is a type of security measure known as challenge-response authentication. CAPTCHA helps protect you from spam and password decryption by asking you to complete a simple test that proves you are human and not a computer trying to break into a password protected account.
A CAPTCHA test is made up of two simple parts: a randomly generated sequence of letters and/or numbers that appear as a distorted image, and a text box. To pass a the test and prove your human identity, simply type the characters you see in the image into the text box.
Example image of CAPTCHA and Image CAPTCHA,
Let’s get started with installing and configuring the CAPTCHA module in Drupal 7.
Step #1. Download CAPTCHA module from http://drupal.org/project/captcha.
Step #2. Install and Enable CAPTCHA and Image CAPTCHA.
Step #3. Configure CAPTCHA.
Step #4. Configure the Default Challenge type.
There are two types of challenges:
1. Math : Simple Mathematical problem
2. Image : obscured image for a word
If using captcha for all forms
We can set custom error messages and descriptions.
Step #5. Configure Image captcha
The length and Characters used for the image captcha.
Step #6. Adding more style to the CAPTCHA.
Fonts, Font size, spacing, colours and backgrounds and also add noise etc
Now, you can see the CAPTCHA in your form like,
