Step 1 : Introduction to the question "1. Before money was invented, people used a different process to exchange goods and services. What is this system of trading called?"
...1. Bart 'n' Mart 2. Barter 3. Quid pro quo 4. K-Mart Bartering is trading goods and services without money. This system of exchange may very well date back to the early pre-history of humankind. This system is not unknown today. For example, in many school playgrounds articles are swapped.