As part of the National Oceanic and Atmospheric Administration (NOAA), the National Ocean Service (NOS) has the role of principal advocate for coastal and ocean stewardship in the US. The NOS home page provides access to information about the NOS, news and events, publications and products, NOS programs, the Data Explorer mapping tool, and educational and outreach materials. The home page also provides links to featured web sites and popular NOS information pages, such as Tides Online.