Adhere to System Appearance. Does your application use all the sweetly colored buttons, delightfully shaded windows, and all the other "bells and whistles?"

User Assistance. This is helping the user with the proper "next step" when performing a task. Less guesswork for the user on what to do next makes for a better experience.

This topic is one we will tackle later in this article, but it refers to making sure that your application and the dock aren't fighting it out for supremacy of the screen.

Drawers. Similar to Sheets, this is a "child" window that gives users access to items that do not always need to be present. But when do you use a drawer and when do you use a palette?

Dock Animation. Sometimes animating icons in the dock can be useful in communicating the status of the system or application.

Okay, I just told you what Apple wants you to look out for with window positions, but in the real world, not everyone uses the hiding feature of the Dock, and it is unrealistic to be able to predict where each user will place their Dock at any given day or how large they will have it. However, you can build a feature into your application that allows spacing for the Finder. You can give users the option of where to position their windows and what area of the screen not to cross. I know that BBEdit provides me with this feature, and I wish more developers gave me more control over my windows.

The simple fact is that, when all other factors are equal, where will consumers spend their money? I believe that in the long run, the best looking, easiest-to-use applications will also be the most successful. I think that's why Apple encourages developers to write programs that are 100 percent Aqua-compliant.

Not quite as entertaining as Shrek, but Dock animation can be an important and useful function in your application. For example, Dock animation is a helpful way to indicate the status of your application.

Other examples of these animations might be to show the status of an FTP transfer, the progress of media being digitized, or an updated time signature. And don't forget that users may want to have some control over this, so give them plenty of options, including the ability to turn these functions off.

By building an application that takes advantage of Aqua's many facets, you help ensure that your application will not only look good, but have a chance of becoming a raging success. After a new user clicks on the icon of your program, the first thing he or she sees is the application interface. I know that when I review a product, I am very critical of its visual design. I usually have a short time to learn the new software, so design and ease of use are very important. Aside from those who marvel at the beauty of the command line, most users tend to react the same way.