Regions are, simply, places: not large geopolitical imaginaries like countries, but tangible, on-the-ground places where people live and work. A region may have urban places, rural places, and wild places. Its boundaries may not be exact, and may look different depending on who you are. Typically we say that a region is bigger than a single town, but small enough to have something in common: a shared history, a common geography, some sense of identity as a regional community.
Development is the process of change, through which people try to improve things for themselves and/or for others. Development can aim to achieve different things: economic growth, social equity, modern technology, environmental sustainability. In rural regions, development is often about ensuring there are enough jobs, services, infrastructure and natural resources for everyone to be able to live well.