Being new to SketchUp learning as I go, I use the back arrow quite frequently. But it has disappeared from the bottom left corner of the screen. Does anyone know where it went?
Yes, Undo. There was one at the bottom. Thank you thank you!
You can also use Ctrl+Z and not have to press a button each time.
The OP is using Mac - so Command-Z. Ctrl-Z for Windows only.