Red: The color of blood and, therefore, of martyrdom. Worn on the feasts of martyrs as well as Palm Sunday, Pentecost, Good Friday and celebrations of Jesus Christ's passion.
It was the "west" that was the region of the United States that experienced the greatest increase in population by percentage from 2000 to 2004, since many people found it more affordable to move.
Islamic scientists developed Algebra.
They built the first observatory.
They introduced the modern day Hindu-Arabic numeral system.