what makes "appropriate technology" is determined by context. Therefore, none of these are absolute - they are simply common features that make a technology "appropriate" to a world where many suffer a lack of basic necessities, a lack of money, and lack of equipment and technological expertise. They are also technologies that have a gentle impact on the earth:
- Small, as in Small is Beautiful. Small often means affordable and adaptable, and puts the control in the hands of the users.
- Few moving parts - less to go wrong (similar to the KISS principle).
- Can be built locally
- Easily repaired, by local people with locally available equipment.
- Affordable
- Made with locally available materials