The use of checks can be traced as far back as the 8th century. Checks were originally used by traveling merchants to pay for goods when they were out of the country. The merchant would write a promise to pay the seller when he returned home. The merchant would send money when he returned from his travels. This was necessary because it was difficult and dangerous to carry large sums of cash. As the use of checks became more popular, banks assumed the responsibility of cashing them. A person with a check (usually the seller) would go to the bank and show the proof of debt from the checkwriter (usually the purchaser). The bank purchased the debt for slightly less than it was worth. The checkholder would get most of his money right away, instead of waiting for the purchaser to send it to him. The bank would send for the money from the merchant, and receive the full amount of the debt. In modern banking, the bank doesn't keep part of the money when it cashes a check.