Archive for Usability YSlow performance grade: F (33)

Holy crap. I was bored at lunch time so I started visiting some random brazilian sites and looking at their YSlow performance grades. has a performance grade of 33.

Biggest issues that I can see:

  • Tons and tons of HTTP requests (8 external js files; 9 external css files; 79 (!!!) CSS background images)
  • Most images have a 20 minute expire time
  • No compression is going on for HTML/JS/CSS code
  • Everything being served from the same hostname
  • No minified JS code
  • ETags are enabled

At least they are avoiding CSS expressions :)

Recommendation: Web Design Index book

Web Design Index 7

I was browsing through a local Barnes & Noble tonight and found a great book on web design: Web Design Index 7.

At first I thought it was some book for web design beginners, but I couldn’t be more wrong. It’s a wonderful book full of screenshots of some very cool web site designs. It seems like a perfect book to inspire your work when designing a completely new site or application.

The publisher, The Pepin Press, has more editions of this book, and I’m sure I’ll buy some more after I go through this one.

Data analytics book wishlist

I wish there was a good book on general guidelines for data analytics. Stuff like best practices on how to display historic data, best ways to plot graphs displaying that information, etc.

The book Visualizing Data seems interesting, but it’s too bad that it is a book about Processing, a very specific type of data analysis software.

Show Me the Numbers is another very good book on this topic, and much more general in teaching some of these concepts. Sometimes I felt it was a bit too academic.

Information Dashboard Design is another good book, but it shows off so many examples of bad design when building dashboard modules, that it forgets to also give a few examples of good design.

Calendar of bad usability mistakes, 2008 edition

This is something I found out while browsing around. It’s a calendar that you can print out to put in your office, but it lists a bunch of bad usability mistakes. It changes every year, and this is the 2008 edition.

You can get your own 2008 calendar for free at