electronic, digital and virtual library - is there any difference?

[Jadranka Stojanovski]

Dear colleagues,
I have read many interesting articles about introducing 
new technologies in the libraries, library development and significant 
changes in this field. 
But there is the lack of the consistency in the terminology 
used in those articles. In some papers the electronic, digital 
and virtual library concepts are very different, in some papers only the  
difference between electronic and digital (or virtual) library is 
emphasized, while in many papers all three terms are used as synonyms.

Could you explain me the difference between electronic, digital 
and virtual library?

Thanks in advance.

If somebody find this question more appropriate for another mailing list, 
please suggest me which one.

Jadranka Stojanovski
inf. specialist and Web manager
Library 
Rudjer Boskovic Institute
Bijenicka c. 54 
Zagreb, Croatia
http://nippur.irb.hr