What type of coffee does Starbucks use?

I'm curious to know, could you elaborate on the specific type of coffee that Starbucks utilizes in their beverages? Do they source their beans from a particular region or multiple regions? Are there any specific roasting techniques or blends that they employ to achieve their signature flavor? Additionally, are there any certifications or standards that their coffee beans adhere to, ensuring quality and sustainability? I'm eager to gain a deeper understanding of the coffee origins and processes behind the iconic beverages offered by Starbucks.