what are the differences between plasmid vector and bacteriophage vector?

Plasmid vectors are short bits of DNA or RNA that are inserted into a bacterial genome to confer resistance to a particular antibiotic or provide some gene necessary for the bacteria's survival.  

A bacteriophage vector is a virus that infects a bacterium and inserts its DNA or RNA into the host to provide new genes coding for new proteins. However, bacteriophages frequently destroy its host whereas plasmids don't.  

Also plasmids tend to be smaller than bacteriophage vectors.  Plasmids are usually 1,000-10,000 bases where bacteriophages can be as big as 500,000 bases.

well, one is plasmid and another is bacteria..

PEACE =D