Arabica and Robusta are the two main types of coffee beans that differ in a number of characteristics:
1. Taste and aroma:

Arabica usually has a more complex and subtle taste with acidity and fruity notes. Robusta tastes rounder, with a distinct bitterness and earthy undertones.

2. Caffeine:

Robusta has about twice the caffeine of an Arabica. This makes Robusta stronger and more bitter when pure. Arabica typically has a lower caffeine content, which allows its more complex flavor properties to stand out.

3. Tolerance to growing conditions:

Robusta is a more robust and long-lived plant, able to grow in a variety of climates. Arabica is more demanding of altitude, climate and soil, and it usually grows at higher altitudes.

4. Price:

Robusta is usually sold at a lower price than arabica, because robusta is a more affordable and yielding type of coffee.

5. Usage:

Arabica is more commonly used for high-end coffees and specialty blends, while Robusta is more commonly used in cheaper, mainstream coffees and blends where more body and strength needs to be added.

It is important to note that there are other types of coffee beans, not just Arabica and Robusta, and some coffee varieties can be blends of these two types with other varieties added.