World 8 · Debt & borrowing · Lesson 3 of 10

Credit and credit cards

What credit is, how lenders decide, and why a credit card is both a tool and a trap.

7 min read · Level: Foundation · Free — no account needed to read

The idea

Credit is the ability to borrow, based on a lender’s trust that you will repay. Lenders judge that trust using information such as your income, existing debts and repayment history. In many countries this history is collected by credit bureaus and summarised as a credit record or score, which affects whether you can borrow and at what rate.

A credit card is a flexible line of credit: you can borrow up to a limit, repay some or all each month, and borrow again. Used carefully — paid in full every month — a card can be convenient and even build a good credit record at little or no cost. Used as a way to live beyond your income, it becomes one of the most expensive forms of borrowing, because unpaid balances usually carry high interest.

Why it matters

Credit shapes your options for years. Understanding it helps you build a good record and use cards as a tool rather than a trap.

A real example

The situation

Mariam uses her credit card for everything and pays only part of the balance each month, assuming that is how cards work.

What happened

When she sees how much interest she paid over a year, she switches to paying the full balance every month and using the card only for planned purchases. Her interest costs drop to zero.

The takeaway

The same card became cheap and useful once it was paid in full.

How people actually behave

Cards make spending feel less real than cash, and the credit limit can feel like available money. Research suggests people often spend more with cards than with cash.

Common mistakes

• Treating the credit limit as money you have.
• Carrying a balance month to month on a high-interest card.
• Missing payments, which damages your credit record for years.

Questions to think about

• Do you pay your cards in full each month? If not, what stops you?
• Do you spend differently with a card than with cash?

Try it: Card check

1. Look up the interest rate on any cards you have.
2. Check how much interest you paid in the last year.
3. Decide on a rule: pay in full, or a plan to clear the balance.

Words in this lesson

• Credit — The ability to borrow, based on a lender’s trust that you will repay.
• Credit card — A card that lets you borrow up to a limit, repay some or all each month, and borrow again.
• Credit score — In many countries, a number summarising your borrowing and repayment history, used by lenders to decide whether and on what terms to lend.