In accounting, a credit is an entry on the right side of a ledger account. Credits increase liabilities, equity, and revenue while decreasing assets and expenses.
For example, when a customer pays $5,000, you credit the Revenue account (income goes up). When you take a bank loan of $50,000, you credit the Loan Payable account (liability goes up) and debit Cash (asset goes up).
Credits always pair with debits in the double-entry system. The word comes from the Latin credere meaning "to believe" or "to trust."