What does l'shana tova mean?

I read that in an email newsletter I subscribe to...what does L'Shana Tova mean?

L'shanah Tova! -- may you have a good new year

It's a Judiasm saying.

...Ok...so, this is new year for Jewish people then? (sorry, didn't know).

Oh I have no clue, I'm not jewish, I dont know much about them either.
That's just what came up when I searched for the meaning. It could be though, I know some places, their year starts at different times than ours does. So it's possible.
Or maybe their just getting ahead of the game early lol.

It's Rosh Hashanah

The Jewish Holiday of Rosh Hashanah is widely known and celebrated as the New Years Day of the Jewish calendar, but actually Rosh Hashanah has a fourfold meaning - It is the Jewish New Year, the Day of Judgment, the Day of Remembrance, and the Day of Shofar Blowing.

http://www.holidays.net/highholydays/rosh.htm

it means To a good year
It's the greeting for Rosh Hashanah, the Jewish New Year. Instead of using the solar calendar, Jews use a lunar calendar with different months. Rosh Hashanah usually falls around September/October. It starts tomorrow night.