The U.S. government announced Monday that it will revise the Home Affordable Refinance Program (HARP) which would allow underwater homeowners to refinance their mortgages. But will the HARP overhaul affect the housing market and the economy at a whole? Here are 5 things you need to know about HARP.

What is HARP?

The program, introduced in 2009, allows homeowners who are underwater, or owe more than the home is worth, the ability to refinance. HARP will cut fees for homeowners who refinance into short-term mortgages.

Who is eligible for HARP?

The refinance plan is only available for borrowers who have primary residence mortgages backed by Fannie Mae or Freddie Mac no later than May 31, 2009 and have been current on payments for six months with no more than one late payments.

How and when will HARP be available?

Full details will emerge from Fannie Mae and Freddie Mac by Nov. 15. Borrowers can contact lenders that offer HARP like Chase Bank and mortgage lender Genworth, who according to NASDAQ will be participating.

How will it affect the housing market and the economy?

Some say HARP will ease the financial burden on homeowners by eliminating hurdles in the refinancing process and saving up to $2,500 each year. Other say it will actually cost homeowners, as in the past HARP has only helped a small percentage of Americans and has included thousands of dollars in closing costs. Obama touted the plan as a small way to boost the economy, like the student loan plan, while Congress debates other issues.