The color of blood and flesh, red is the color of life. And red is thus linked to all the emotions of life.
It shows people's determination to act. It's the color of the life drive, but also of struggle and self-assertion.
But red also marks acceptance of life, respect for life and love for life.
Red is the color of speed and sports cars, and the color of life actions: the red cross.
Red is the color of combat, whether revolutionary or in the arena.
And it's also the color of sex and violence, the color of fire that burns passions.