Difference between h1b renewal and h1b extension

Could you please let me know which one would be the best thing to opt for i have a h1B till feb 28th 2013, my employer is filing an H1B cap exempt renewal and said would take 3-4 months for processing. But manager asked the immi team if they can extend it without renewing it so that i would be ready to travel much earlier than renewal time. Please suggest me what best can be done , i need to travel in next 3 weeks

You are outside US, right?

I don’t see any difference except in terminology different people use.

Legall speaking, your employer has to file a cap-exempt petition w/ the option of visa being issued at a consulate outside US. After processing it, USCIS will approve it for a certain term which can be beyond your current H-1 expriation date.

So this is renewal as you filed cap-exempt i.e. used a previously approved H-1 petition to skip cap. This is also extension as you get a new end date beyond your current end date on the petition.

Once approved, you will have to appear for visa stamping and get new visa stamp. This assumes you travel after your current H-1 visa stamp expiration date.

Also, from your question it looks like employer is not in a position to explore the option of you entering US in next couple of days and then filing the petition from within US.