H1B renewal/extension one year after expiration

I got H1B approval for one year in Jan 2012 (which got expired in Jan 2013). But I left the job and came to India in June 2012. Now can the same employer file for an extension given that the visa got expired less than a year back ? And has it anything to do with the duration ? Or do I have to apply for a fresh H1B ?

Can another employer file for tranfer and extension ?

PS: I am not completely sure how renewal differs from extension.

Thanks in advnace.

Same Employer or Different Employer can file a Cap-Exempt Visa for U anytime.