Strokes can be sketched and erased easily allowing you to quickly get your design concepts underway.
It is best if strokes overlap at the corners, however, strokes that almost intersect also work fine too.
Using the Edit Toolbar you can switch between the Pencil and the Eraser to determine your current mode.
However, while Pencil mode you can also use a squiggle to quickly erase strokes:
When erasing strokes, these are automatically trimmed to the nearest two intersecting strokes.