Subprime Mortgage definition

What is subprime mortgage exactly means? Will it really make US and the global world into a big recession ?
Here is the definition of Subprime Mortgage, which in Indonesian means "Krisis Kepemilikan Rumah"

Subprime Mortgage definition from Wikipedia :

The subprime mortgage crisis is a current economic problem characterized by contracted liquidity in the global credit markets and banking system. An undervaluation of real risk in the subprime market is cascading, rippling and ultimately adversely affecting the world economy.

The crisis began with the bursting of the US housing bubble and high default rates on "subprime" and adjustable rate mortgages (ARM). Loan incentives, such as easy initial terms, in conjunction with an acceleration in rising housing prices encouraged borrowers to assume difficult mortgages on the belief they would be able to quickly refinance at more favorable terms. However, once housing prices started to drop moderately in 2006–2007 in many parts of the U.S., refinancing became more difficult. Defaults and foreclosure activity increased dramatically, as easy initial terms expired, home prices failed to go up as anticipated, and ARM interest rates reset higher. Foreclosures accelerated in the United States in late 2006 and triggered a global financial crisis through 2007 and 2008. During 2007, nearly 1.3 million U.S. housing properties were subject to foreclosure activity, up 79% from 2006.

Subprime Mortgage definition from About.com :
Definition: A subprime mortgage is granted to borrowers whose credit history is not sufficient to get a conventional mortgage. Often these borrowers have impaired or even no credit history. These can also include interest-only loans.

The subprime mortgage crisis is threatening to put the U.S. economy into a recession. This primer it tracks how the subprime crisis unfolded, affecting first the real estate market and now the economy overall. It gives you definitions of important terms. It also explains how interest rates and real estate play an integral role in the U.S. economy. Finally, it gives resources for those who are suffering from the subprime mortgage crisis directly.