Using Only Simple Mouse Operations
When possible, you should require only single-clicks to perform common operations. Some users have difficulty holding down a mouse button while moving the pointing device, and this makes drag-and-drop operations difficult. Double-clicking is also more difficult than single-clicking, so you should provide single-click access to commonly used operations whenever possible. You should also avoid requiring the use of mouse button 2, because some pointing devices and many alternative devices used by people with disabilities do not support it.