When you load the menu option, the values you see displayed will be the values currently in use by your game. Vanilla values are 3.3 and 2.0. If the menu is displaying different values, then you have a mod installed which is already adjusting these two settings. If you choose to select a new setting, Trade & Barter will override the settings from the other mod. If at any time you wish to revert the settings back to those made by another mod, simply deselect this setting and reload your game. You will need to reload your game before the changes from Trade & Barter are fully canceled out.
Though trade and bartering are both methods that have been used for the purpose of obtaining required goods and services over the years, there is some difference between barter and trade. That is, while bartering involves the exchange of one product for another, trade involves exchanging money for goods. Trade is also conducted in commodities, currencies, stocks, etc. Trade and bartering may sound similar but there are a number of important differences between barter and trade. It is important to clearly understand each concept in order to grasp their similarities and differences. The following article offers a detailed overview of each and highlights their similarities and differences.
Trade did occur in non-monetary societies, but not among fellow villagers. Instead, it was used almost exclusively with strangers, or even enemies, where it was often accompanied by complex rituals involving trade, dance, feasting, mock fighting, or sex—and sometimes all of them intertwined. Take the indigenous Gunwinggu people of Australia, as observed by the anthropologist Ronald Berndt in the 1940s: