iPhone Human Interface Guidelines

Apple has published an iPhone Human Interface Guidelines
document. Guidelines has details on user environment, principle and guidelines for iphone content, metrics, layout guidelines and tips.
Apple’s iPhone presents a revolutionary user interface and interaction model. Users can view webpages, use web applications, and use built-in iPhone features, such as the email application, the iPod, and the digital camera, wherever they go. Safari on iPhone, a unique implementation of Safari, is the application users use to browse the web on both iPhone and iPod touch. more ...

PDF version is available here.

Few irritating captcha's - Image verification

"Oh God! Its irritating. Am trying to finish this form, but this image-verification is killing my time and patience. "

This is not from my mouth. This is what I have seen some user say while filling forms in few websites. The worst part is they don't understand the characters in image. Some time its so tough that they don't understand 50% of the characters. We all know that Captcha helps preventing the softwares from autofill.

Another user says

"I tried to change the captcha and whole data is lost. Again i have to re enter the data. Then once again captcha is not clear & I clicked 'show different image' and whole page refreshed and all the datas I entered was lost and I never filled the form in that website & all my friends faced the same issue."

"CAPTCHA" is an acronym for "Completely Automated Public Turing test to tell Computers and Humans Apart", trademarked by Carnegie Mellon University. - Wikipedia

Yes - we all have experienced some way of other with different types captcha used in web. Below are some Good and Bad example of captcha.

Good Captchas - easy to understand for users

This captcha is pretty straight forward. User need no second thought.

Look at this recaptcha, its so simple and user has option to listen to audio on worst case.

Pretty straight forward

Its simple & no issues in understanding the text from image.

Next two is from msn. Some images are difficult to understand, but its rare. Its also accessible for users with disabled. Even normal users can user the audio to enter the information

Another screen shot from msn.

This is from Google. Very-very easy to understand and also easy for visually challenged.

Bad Captcha - by which user gets irritated and big loss for business

Oops - Captcha with encryption. its time consuming and prone to mistakes. And its not accessible & easy to use for visually challenged.

Below image is readable, but not accessible. No audio facility.

Oops - one of the worst.

Ooops - not again, this captcha is bad.

facebooks captcha- few characters are difficult to understand. Below one is easy though.

Universal Principles of Design

I recently read this book in borders. This is an awesome book written by William Lidwell, Kritina Holden, Jill Butler. Its available in Amazon.

Universal Principles of Design: 100 Ways to Enhance Usability, Influence Perception, Increase Appeal, Make Better Design Decisions, and Teach Through Design.