What's the main difference between "boundary" and "border"?

Native speaker’s answer
Rebecca
A "border" is an outer edge of an area or space. You may have a border for something within a larger area. A "boundary" is a line that divides two areas. Ex: The border for the garden is two meters away from the boundary of the house! That means there's enough room to walk around the garden. Ex: My painting needs a border, so I always leave a centimeter or two on the edge of the page blank. Ex: Make sure you don't go out the boundary lines when playing the soccer game, Tim. Otherwise, you could lose a point.