OK, you've finally started getting your loans in order. You used the National Student Loan Database System to see what you've borrowed from the feds. You've consolidated, if appropriate, and picked an income-based repayment plan so that your payments are manageable. You're also up-to-date on your monthly payments on any private loans.
But now your career is taking off and you have a bit of surplus cash. And instead of letting the interest build on those loans, you're ready to start dumping your excess cash on one or more of them.
Which one do you pick first? That depends on a few considerations.