• Reduced learning curve: Forget about learning so many Web applications out there
• Nice User Interface and localized to many languages
• Fast and secure
• Active development

The term CAPTCHA, based upon the word Capture, is a type of challenge-response test used in computing to ensure that the response is not generated by a bot. The process usually involves one computer asking a user to complete a simple test.

Using a CAPTCHA Script on a website is a great way to ensure that response is made by a real person and not by a spambot and it helps prevent automated abuse of your site such as comment spam.

There are many CAPTCHA scripts available, lets dig into the list together.

Image Based CAPTCHA

Fresh & Creative Alternate to Traditional CAPTCHA Scripts – slideLock

slideLock adds a jQuery UI slider along with labels and notes. The user simply slides the form to unlock the submit button and then both client side and server side validation techniques ensure secure submission of the form.

reCaptcha

Stop spam and help digitize books at the same time! The words shown come directly from old books that are being digitized.

Photo CAPTCHA System – identiPIC

identiPIC is a photo CAPTCHA system whereby a website visitor has to identify a picture to proceed. The system is typically used on web forms to block spambots.

s3Capcha jQuery Plugin

A lightweight CAPTCHA jQuery plugin which works with a simple click.

Ajax Fancy Captcha

Ajax Fancy Captcha is a jQuery plugin that helps you protect your web pages from spammers. If offers an intuitive way of completing “verify humanity” tasks. In order to do that you are asked to drag and drop specified item into a circle.

Clickcha – The One Click CAPTCHA

Clickcha is a unique CAPTCHA system that more secure than traditional text based CAPTCHAs yet easier to use. Clickcha is currently available as plugin for WordPress and bbPress. It can also be integrated into any CMS using the simple Clickcha API.

MooTools Bot Filtering CAPTCHA Class

Don’t read, just drag the right option into the block hole.

Open Source PHP CAPTCHA Script

Securimage is an open source free PHP CAPTCHA script for generating complex images and CAPTCHA codes to protect forms from spam and abuse. It can be easily added into existing forms on your website to provide protection from spam bots. It can run on most any webserver as long as you have PHP installed, and GD support within PHP.

Image Based CAPTCHA

It uses a distorted point for human verification. It is easy to notice a slightly distorted point over an image. Its obviously a good option to click once instead of typing 5-6 letters. Look at the demo for better understanding.

Flash Based CAPTCHA Script – Internet Captcha

Internet Captcha is a flash based CAPTCHA script for ASP and PHP designed to protect your HTML forms. It comes with a friendly configuration screen to edit interface and security level.

More resources:

• http://captchator.com
• http://www.tipstricks.org – Classic ASP based CAPTCHA
• http://www.spamerator.com – Spamerator can be integrated with any language including PHP, VB, ASP/.NET, Java.
• http://www.captcha.cc – Free service to place very hard CAPTCHA images in front of a form submission.
• http://www.textdisguise.com
• http://rodomontano.altervista.org/engcaptcha.php – Static and animated CAPTCHA script generator.

Text Based CAPTCHA Scripts

textCAPTCHA

Its a web service and comes with a unique API. Whenever you require a logical question, it requests to the server and the server returns an XML response containing a randomly selected question and answer.

PHP Text Captcha

A method of using a question / answer CAPTCHA system for determining whether one is dealing with a human visitor or a naughty robot.

Open Source Javascript Library for Client-Side Validation

LiveValidation is a small open source javascript library for making client-side validation quick, easy, and powerful. The technique used in this Javascript Validation Library can be implemented as a CAPTCHA.

Further readings:

• MathGuard PHP form anti-spam protection – Comes with an expression consisting of two random numbers, one text input field for user’s answer, and one hidden field with the hashcode.
• A better CAPTCHA Control – This Free CAPTCHA control generates numbers and letters which are HTML and not an image.

SVNKit is a pure Java Subversion toolkit that implements all Subversion features and provides APIs to work with Subversion working copies, access and manipulate Subversion repositories.

SVNKit is a programmatic solution to use version control in Java applications, can be used as:

• an integration tool to work with versioned data in a standard way (using WCs)
• an Engine to speak to a Subversion repository on a repository access protocol layer

SVNKit features

• Repository access over http(s), svn, svn(+ssh) and file protocols
• Repository administration
• Does not require additional binaries
• Turns contents of a repository to a portable dump format stream

Teambox’s overview screen is a Twitter-like feed of activity and updates. You can post updates on a project. Stay in touch with your team all the time, across all your projects, easily.

This project management software supports:

• Multiple projects
• Status updates
• Document attachments

This open source software is written in Ruby on Rails and you can use a hosted version or can download a copy to host your very own.

You can watch and organize video feeds when you’re offline or traveling. Miro downloads in HD, whenever it’s available!

You can search and download videos from:

• Youtube
• Google Video
• Hulu
• Blip and many more…

Miro downloads video fast and stores it on your local computer for a level of quality that is often impossible on streaming video websites.

As this open source video player downloads most videos so you can take your shows with you, wherever you go and can see whenever you want.

This open source social networking engine allows you to connect with and follow other people and topics and send private messages to each other.

OSQA can be used as:

• An online forum
• Support / Help desk platform
• Basic project collaboration platform
• Simple Content Management System (CMS)

OSQA supports themes, embedding videos / audio / images and empowers you to import data from your current or old Stack Exchange site.

You can draw multiple plots in the same timeplot, either using the same geometry of another one or not, depending on what you want to achieve.

With this open source data visulization widget, users can create timeplots which are very easy to customize.

• Stroke and fill Plot colors customization
• Multiple timeplots
• On-Demand plot values

Here is a list of free and open source tools and plugins that can help us to test performance and speed of our websites. With their suggestions, we can improve site’s response time.

 Website speed check

The website speed tester shows the duration of a given website. This value can be used for showing how long a website take to load and if it is better to optimize the website or change a (slow) ISP.

BrowserMob – Free Website Performance Test Tool

Test your website performance with this free cutting edge tool. This tool accesses your website from different location and generates a website performance analysis report.

PageTest

Pagetest allows you to provide the URL of a webpage to be tested. The test will be conducted from the location specified and you will be provided a waterfall of your page load performance as well as a comparison against an optimization checklist.

Compare site performance

Webslug is a tool of identifying potential problems with your website’s performance. Compare your site with your competitors or simply check yours to get some insight.

Open Source Speed Test Tool – Fancy Speed Test

Customizable open source speed test tool that performs upload and download bandwidth tests and provides Interactive user experience. To drill down more, users can restrict to particular networks / IP addresses.

Pingdom Tools

Test your page with Pingdom Tools, It’s Page Test loads a complete HTML page including all objects (images, CSS, JavaScripts, RSS, Flash and frames/iframes). The Load time of all objects is shown visually with time bars.

Site Performance Testing Tool

Get an accurate, realistic and helpful estimation of your site’s loading speed with this smart website performance testing tool. This free tool offers many features like:

• Tests from around the world
• Advanced on-the-fly HTML parsing
• Smart parallel downloads
• HTTP-compression support
• Keep-Alive support

Web Page Analyzer

A free web site speed test tool to improve website performance. It calculates page size, composition, and download time. Based on the final results it offers advices on how to improve website’s weak areas.

Self SEO

A small but handy website speed test service by self SEO. If you don’t want to dig into details, it’s a best choice to just get yourself aware about how much time your site took to load.

YSlow by Yahoo!

YSlow analyzes web pages and suggests ways to improve their performance based on a set of rules for high performance web pages. YSlow is a Firefox add-on integrated with the Firebug – A web development tool.

Page Speed – Open Source Firefox / Firebug Add-on

Page Speed is an open source Firefox / Firebug Add-on. Webmasters and web developers can use Page Speed to evaluate the performance of their web pages and to get suggestions on how to improve them.

Pagetest – Open Source Web Performance Testing Tool for Internet Explorer by AOL

Pagetest is an open source tool for measuring and analyzing web page performance right from your web browser. This is a powerful tool for web developers and software engineers in testing their web pages and getting instant feedback.

Website & Server Speed Checker Tool from Vertain Software

Free instant website & server speed test. Track speed variations with our automated speed tests. Evaluate your site’s performance against your competition.

Webwait

WebWait is a website timer. You can benchmark your website or test the speed of your web connection. Timing is accurate because WebWait pulls down the entire website into your browser, so it takes into account Ajax/Javascript processing and image loading which other tools ignore.

Supports multiple data representations like Treemaps, Radial Layouts, HyperTrees/Graphs, etc…

InfoVis components are:

• Powerful and easy to use
• Support live data updates and multi-valued data
• Mutable Visualization classes & can add/override any method
• Useful for combined visualizations

This JavaScript Interactive Data Visualizations Toolkit is open source and can be used with your favorite DOM manipulation framework.