virtuoso中的bBox是什么

just like the title,what is the meaning of BBox in virtuoso?And it's use for what?
thanks for your help！

bounding box

what is the meaning? it is used for what?on what occasions , we can use it

it is the boundary of a cell. if you set the bbox can't overlap, it means the cell will not overlap.

就是边界，和boundary 意义类似

thank you