Masking

[nala]

I'm still pretty new to PS. What is the difference between creating a mask and using the black paintbrush to "undo" different areas and just using the Eraser tool to erase out the parts you don't want the change applied to?

 

[Buckster]

Using the eraser, the information is gone once you've saved. Using a mask, that information is always there, able to be restored at will. There's also a whole slew of mask modification tweak abilities that the eraser doesn't provide.