credit

Buy a coffee with your card and pay the bill next month; take out a mortgage and pay it back over thirty years; let a customer 'put it on the tab'. In each case someone receives goods, services, or money now and promises to pay later. That arrangement — receiving value today against a promise of repayment tomorrow, usually with interest — is credit. Its other face is debt: credit is what the lender extends, debt is what the borrower owes; they are the same deal seen from opposite sides.

Credit works on trust (the word comes from the Latin credere, 'to believe') backed by the expectation of repayment. A lender hands over purchasing power now in return for a larger sum later; the extra is interest, the price of borrowing and the lender's compensation for waiting and for risk. If you borrow $1,000 at 8% for a year, you repay $1,080: $1,000 of principal plus $80 of interest. Whether credit is granted depends on creditworthiness — the lender's judgement that you will repay — which is why lenders check income, collateral, and credit history. Crucially, in modern banking the act of extending credit is also the act of creating money: when a bank lends, it creates a new deposit, so credit and the money supply expand together.

Credit is one of the great engines of a modern economy. It lets businesses invest before they have saved the full cost, lets households buy homes and smooth spending over a lifetime, and lets good ideas get funded today rather than decades from now. But credit cuts both ways. Borrowing brings future income into the present, which means future income must service the debt; too much credit can fuel asset bubbles and leave borrowers fragile, and the boom-and-bust of credit cycles — easy lending followed by sharp contraction — is at the heart of many financial crises. Credit is powerful precisely because it is leverage, and leverage magnifies both gains and losses.