Nobody sees Santa Claus, but that is no sign that there is no Santa Claus. The most real things in the world are those that neither children nor men can see.

The Santa tracker site receives millions of visitors from around the world each year, according to NORAD, and volunteers typically answer more than 130,000 calls.

While public anxieties have loomed over the Northeast amid possible drone sightings, one sighting will soon bring holiday cheer across the country: Santa Claus.

NORAD, which is responsible for protecting the skies over the United States and Canada, activated its Santa tracking system at 6 a.m. ET on Christmas Eve.

The Santa tracker site receives millions of visitors from around the world each year, according to NORAD, and volunteers typically answer more than 130,000 calls.

In the US, it's common for children to leave Santa Claus milk and cookies. But this tradition looks different for children around the world. In Ireland, some families leave Santa a pint of Guinness.