Here's a comprehensive summary of the Wikipedia article on credit:
Credit: Trust, Debt, and Modern Money Creation
Credit, derived from the Latin "credere" (meaning "to trust"), is a fundamental financial concept where a lender provides money or resources to a borrower with the promise of future repayment, thereby creating a debt. Historically, credit evolved from 19th-century agrarian communities using store ledgers to the widespread emergence of company-issued credit cards in the 1900s. Significant milestones include the 1958 introduction of bank-issued cards like Bank Americard and American Express, which popularized "revolving credit," allowing consumers to pay off balances over time with interest. However, access to credit was not always equitable; until the 1974 Equal Credit Opportunity Act, women and people of color often faced severe discrimination in obtaining financial loans. In modern economies, banks are the primary creators of money, generating the vast majority of currency as credit when they issue loans, which subsequently disappears from circulation once the debt is fully repaid.