A declaration you are making to visitors of your website about how you are gathering information about them and what you intend to do with it.
The Internet is not a private place, but there are certain expectations consumers have.
Depending on what your website is about - the Federal Gov may also have an action to come say hello (and not in the hey, what's up way....)
Most countries have such laws, and the Canada and the EU have some pretty extensive requirements.
If you have a website collecting emails, make sure you have this in place!