MovingtimeMortgage.com

A mortgage is a big decision for most households.  You always want to get the best rate on your mortgage
without a large up-front cost.  Depending on the amount of time you'll be spending in the home you are financing will determine the  soundness of your decision to pay the up-front fees or not.  Discount points simply increase the yield to the lender.  The amount a borrower will pay in discount points is negotiable and determined by the long term rate of interest that will be paid.  For each point (one percent) paid to secure the loan, the yield to the lender is increased by 1/8 of a percent over the life of a typical 30 year mortgage.  Only buy down the rate, if you will be in the home for a long period of time.  There are many definitions of mortgage on the Web:

a conditional conveyance of property as security for the repayment of a loan
www.cogsci.princeton.edu/cgi-bin/webwn

The one I like best is very simple:
A legal document that pledges a property to the lender as a security for payment of a debt.
www.calpers.ca.gov/homeloan/program/mhlgloss.htm