what's the mean of the method named Rigidbody2d.cast()?

I’ve seen the documentation for several times but I can’t still make it understood at all.It says , “All the Collider2D shapes attached to the Rigidbody2D are cast into the scene starting at each collider position ignoring the colliders attached to the same Rigidbody2D”.
What’s that mean?And I’ve try to experience it for several times and it doesn’t result in any effect or any work.
Can someone help me?Thanks a lot!

Ohoo… didn’t even notice this Method before. Looks like we finally got a 2D version of Rigidbody’s SweepTest.

Basically, Unity shoves your Rigidbody’s shape into the specified direction and sees what it would collide with. No events are triggered since it’s not actually moving your Rigidbody. It’s nice to check if your object fits through an area or where and with what it would collide.