The term “appropriate technology” refers to any method or equipment that is powerful enough to accomplish the task at hand, and not more powerful than that.
A tank is appropriate technology for attacking an enemy stronghold, but it is not appropriate for a trip to the grocery store. For that task, appropriate technology would be a car, a bicycle, or even our own two feet, depending on how far away the store is and how much we plan to carry back.
As another example, a huge mowing machine might be appropriate technology for harvesting acres of corn, but it is too big and powerful for maintaining a suburban lawn. Whether a residential-size ride-on mower, a gas-powered push mower, or an unmotorized mower is most appropriate depends on the size of the lawn and the physical ability of the owner.
As a general rule, appropriate technology is smaller, quieter, simpler, and less polluting than too-powerful technology. When we choose appropriate technology, we save money, conserve resources, and make our neighborhoods more peaceful places to live.