I'm going to assume you mean drawing software, so,
It's called the lasso, or selector.
Answer:
A line in art is defined as a point moving in space, and it's one of the seven elements of art (line, color, shape, form, texture, value, space).
Sure I can help you if you really think about it all of it means just ANB
Stylization.
It’s used when an artist wants to step away from the conventional representation of their chosen subject or concept.
Best of luck :)
