According to the traditional account of knowledge: S knows P iff S has a (1) Justified (2) True (3) Belief. I have not faced any account of knowledge that denies that last two things (epistemic property I may say?) namely S believes P, and P is True. Everybody seems to have a problem with justification.
Now, according to Plantinga, Warrant is something that makes a distinction between true belief and knowledge.
Can't we just say that he gave us a new sense of justification or he redefined justification? What is the difference between justification and warrant then? We use justification when studying Gettier, Harman, Lehrer etc. and we use warrant when studying Plantinga? Is that it?