Bacteriophages are a better vector than the plasmids due to the following reasons: It can clone the DNA segment of a relatively large size (24 kbp). Every bacteriophage produces one plaque area in the culture through which testing is comparatively easy. λ (Lambda) phage is more widely used as a vector than $$M_{13}$$phage because λ phage is having linear and double-stranded DNA and it is a phage of E.coli and large-sized foreign DNA can be easily inserted in it's DNA.