Need to Return the Background from Grid to Blank

[bearspencer]

I was working on a Word 2007 doc and accidentally hit a couple of keys.
The normally blank background suddenly became a grid.


I exited the document without saving it and closed the program.

When I opened the program grid background appeared on the
document I was working on, previously saved document and
newly created one. But the gridded background does not appear
when I open Print Preview.

How do I return to blank?

Screen shot attached