That happens to be the motto of the United States and it means, "Out of many, one."
Originally referencing the pulling together of thirteen separate and independent states into one nation under the Constitution, it has come equally to apply to the diversity and community that exists in this "nation of immigrants."
In the face of division happening in the country recently, I love the gesture of Kent State basketball players tonight. They went into the stands and brought people of varied backgrounds onto the court with them for the national anthem. Full story here.