Zietgeist

Zeitgeist, what is that all about? Is that some sort of film or religious concept. I heard someone talking about it the other day, something about the calendar is missing certain days, Jesus's birthday is on a different day or something like that, and a lot of other spiritual, hoodoo voodoo stuff I can not really remember right off hand. And doesn't the word "Zeit" mean time in German? So maybe its some spiritual philosophical time. But I do remember it was some sort of awesome mind blowing stuff. Maybe I should call that person and ask them what the heck they were talking about so I can sort of make sense with this blog entry. And maybe that internet bible dictionary Wikipedia may have an answer for that to answer all of my what does that mean questions.