In this paper, the authors think that all of traditional library, electronic library, digital libraty and virtual library have basic attributes of library, with different names for comparative differentiation.

• 传统图书馆、电子图书馆、数字图书馆和虚拟图书馆 ,均具有图书馆的基本属性 ,其不同称谓是相对而言 ,如数字图书馆是相对于数字化技术应用于图书馆而言。