In this reposity you can see the code of my dissertation in R programming language. More specigically, I took Covid19 data for many countries around the world in the time between 2020 and 2022 and I used it in order to see how Covid19 hit these countries in a epidemiologically way. Also, I saw a difference in the hit of Covid19 in some countries. In this project I used Principal Component Analysis and Cluster Analysis.