In this talk we will tell the story of Meltdown and Spectre. We will outline how research from the past two decades was the foundation of the discovery of these vulnerabilities while providing preliminary information. We will point out and illustrate how what the root causes of Meltdown and Spectre are. In the main part of the talk we will describe how Meltdown and Spectre work. We will discuss different attack scenarios and the impact of these attacks. Finally, we will outline countermeasures against the attacks.