Arabica and Robusta are the two main species of coffee beans. Arabica beans are considered higher quality and have a smoother, sweeter flavor with notes of fruit and sugar. Robusta beans have a harsher, more bitter taste with higher caffeine content. Arabica beans are more delicate and challenging to grow, while Robusta beans are hardier and easier to cultivate. Most specialty coffee is made from Arabica beans, while Robusta beans are often used in instant coffee and espresso blends.