Google is offering additional protection for its "strict" SafeSearch options. When you receive the update, you'll be required to give your password to select the strict option or to change it back to moderate or off.
When the strict SafeSearch is selected, bright bubbles with the primary colors of Google's famous bubble will be present in the top right corner of the page.
This means parents can keep an eye on their kids' web browsing without breathing down their necks.
For more info, check out this video Google put together: