Designing click targets for better usability

Jensen Harris, writer of official Microsoft Office blog Giving You Fitts, explains Fitts law (the time required to move from one position to another is a function of the distance to and the size of the target) and how it affects interface design.

Most importantly, Harris states, is how increasing screen resolution has negatively affected people's ability to quickly "hit" a target with a mouse cursor.

Using text with an icon is more usable because the target is larger. Making toolbars more compact - multiple rows in floating rectangles - makes the distance from cursor to icon shorter and, therefore, faster.

As evidence of how design changes work, Harris provides examples from the redesign of Office 2007.