President Barack Obama has begun his second term by declaring that the nation's "possibilities are limitless." Speaking before a flag-waving crowd of hundreds of thousands on the National Mall, Obama said, "We are made for this moment, and we will seize it, so long as we seize it together." In his second inaugural address, Obama didn't dwell on any first-term accomplishments, but instead looked to hard work ahead in a country still grappling with a sluggish economy. And he urged Washington to find common ground over his next four years. Obama earlier placed his hand on two Bibles -- one that was used by Martin Luther King and the other used by Abraham Lincoln -- and recited the oath of office. Vice President Joe Biden was also sworn in for his second term.