A lender is an individual, a public or private group, or a financial institution that makes funds available to a person or business with the expectation that the funds will be repaid. Repayment includes the payment of any interest or fees.
The lender credit offsets your closing costs and lowers the amount you have to pay at closing. In exchange for the lender credit, you will pay a higher interest rate than what you would have received with the same lender, for the same kind of loan, without lender credits.