The first banknotes were made in China in the 7th century and were made of leather. Notes didn’t become paper until 400 years later.
The original banknote from the Bank of England was a receipt for coins. A customer would come into the bank, deposit their coins and was given a hand-written ‘ticket’ for that amount. This was a promise to pay the ‘bearer’ of the receipt (the person who presented the ticket). British notes still have the words, ‘I promise to pay the bearer on demand the sum of …’ on them. It was not meant to be money. It was an ‘I Owe You’ (IOU).
Notes are much less durable and can’t survive in rain, for example, their other main disadvantage is that they can be copied.
Credit cards are the best thing that ever happened to people who want to buy things they cannot immediately afford, yet credit cards are also the worst thing for the same people because they can easily put you in debt.
Being ‘in debt’ means you owe money and when you owe money, you pay interest on what you owe. Interest is usually a very small percentage of what you owe but to give you an example: if you were to buy a new smartphone for 300 dollars/pounds/euros using a credit card and paid off 30 dollars/pounds/euros each month on an average-rate credit card, you would end up paying around 350 dollars/pounds/euros for the phone.