Something is going to happen.
Not the end of the world though.
So every month we enter a new sign of the zodiac. Aries, Pisces etc. This is based on the Sun, the Earth and whatever constellation is lined up with them.
The sun also rotates around a much bigger star. The Sun and the bigger star also align with constellations. Every 2000 years or so based on this alignment the sun enters a new constellation know as an age.
When the Myans wrote their calendar they choose to end it when the sun entered a new age. On the 21st The sun leaves the age of Pisces and enters the age of Aquarius.
So in one week's time all that is going to happen is the sun enters a new constellation. If history tends to repeat itself, in the years to come life as we know it will change. But nothing major will happen in 7 days.
The only reason it was hyped by the media is so people will go buy supplies from wal mart.
tl;dr quit being so lazy but please comment before reading anyways.