Way to make it so the public can not edit the sheet?

Way to make it so the public can not edit the sheet?

Hi there,

I am new to Zoho and am playing around with the sheet features. So far so good. I just uploaded and made public a random excel spreadsheet and then logged out to view how the public would see it. I was able to add to the cells even when not logged in. Is this a feature that can be suppressed? Or is it something that will just be on their spreadsheet?