The main difference between Chapter 7 and Chapter 13 bankruptcy is in the way the debt payment is structured.
Under Chapter 7 a debtor's assets are sold off to pay the lenders (creditors) in a process called liquidation.
Chapter 13 on other hand is more of a negotiation since debtors filing under this chapter still receive a regular income and with that they can negotiate a payment plan to repay the loan without having to liquidate all of their assets.