The first person to earn a PhD in computer science was Edsger W. Dijkstra in 1951. His dissertation, titled "A Note on Two Problems in Connexion with Graphs," laid foundational principles for computer science and established him as a pivotal figure in the field. Dijkstra is renowned for his contributions to algorithms, particularly the Dijkstra's algorithm for shortest paths, and for advocating for structured programming. His influential work shaped the development of programming languages and the discipline of computer science as we know it today.