A mortgage is a type of loan where the purchased property is used to guarantee the loan.  The guarantee is viewed as a lien against the property and is recorded as a public record.

You enjoy full title to the property as the borrower with a mortgage but the lender has the right to sell the property if you do not pay your debt.

Lender

A lender is any entity that loans money.  Lenders are usually banks or private financial groups.

Mortgage Broker

A mortgage broker is a financial specialist that seeks to find the best loan for you.  The broker does not work for one lender.