If you own a WordPress blog and you want to make sure that comments posted on your site were generated by a person, not by scammers or programmed bugs, then a proficient tool you may utilize is a CAPTCHA. The term stands for “Completely Automated Public Turing test to tell Computers and Humans Apart.” You have probably generated one before. Before you can even post a comment or sign in in a particular website, you will be asked to type in the text box the letters, words, or numbers you see on the screen. The figures are either warped or segmented as part of the high level security, while some websites have audio versions of CAPTCHA. Only humans can read distorted letters and digits, not any current computer programs.
CAPTCHA was coined by Luis von Ahn, Manuel Blum, Nicholas J. Hopper, and John Langford of Carnegie Mellon University. The concept is similar to a simple test or challenge which is automatically generated and assessed by the computer but manually answered by Internet users. The CAPTCHA ensures prevention of comment spam and protection of website registration, email addresses, online polls, dictionary attacks and search engine bots.
So, if you want to utilize an additional security program for your WordPress blog, you may do so by using a CAPTCHA plugin. WordPress ensures the protection and service satisfaction of its users by allowing them to use utility plugins such as CAPTCHA. Users can choose from any of the 254 CAPTCHA plugins ready for download on the WordPress.org plugin directory.
Below are a few recommended CAPTCHA plugins that you might want to try.
1. SI CAPTCHA Anti-Spam. Its latest version 2.7.5 works well on WordPress version 2.9 or higher and PHP5. This CAPTCHA uses an abstract background with multicolored, angled text and arched lines through text. But in case the figures are really difficult to understand, users can click on the refresh button to reload it.
2. NuCaptcha WordPress Plugin. This CAPTCHA does not simply let users identify warped letters or numbers flashed on the screen. In NuCaptcha, users are given more animated challenging tests.
3. Sweet Captcha. This is by far the most user-friendly and interactive plugin I’ve seen. This is excellent for young users because of its design-your-own-Sweet-Captcha feature based on different categories such as music, shopping, movies, etc. The graphics and animation are amazing. In addition, users can customize the CAPTCHA on their preferred local language and it has full mobile support that works well on iPhones, iPads and Android mobiles.
Remember that the criterion in choosing the best Captcha for WordPress must be its accessibility on different CMS platforms, simple configuration and installation instructions, full WordPress support, complete documentation, and most importantly, its interactive design to make your webpage more entertaining, at the same time protected.