As the week continues, we’ll learn more about America’s housing market. But we do know that many of those buying homes are utilizing the 30-year fixed-mortgage rate, which last week was averaging 4.29 percent. In the first half of 2013, 90 percent of new home loans were the 30-year. Why are they so popular?

“[It’s] really pro-borrower,” explains Marketplace’s Adriene Hill. “These are fixed-rate loans with no prepayment penalty, which means you don’t carry risk if interest rates rise or interest rates fall.”

Click the player above to hear about some alternatives to these kinds of mortgages, and the concerns that arise as interest rates change.