Asia is the Earth's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and comprises 30% of its land area. With approximately 4.3 billion people, it hosts 60% of the world's current human population. Wikipedia

North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It can also be considered a northern subcontinent of the Americas. Wikipedia