Michael Atiyah passed away at the age of 89. The Guardian obituary and The New York Times obituary are good places to learn about his background. The Guardian article called him “one of the greatest British mathematicians since Isaac Newton.”
I have written 3 blogposts informing readers about some of Atiyah’s work:
Atiyah’s Grand Survey of Duality in Mathematics and Physics
Atiyah lecture at 2016 Heidelberg Laureate Forum
Atiyah lecture at 2018 Heidelberg Laureate Forum
I am not educated enough to follow his work in technical details but I was inspired by his enthusiasm and intellectual curiosity and his determined effort to find connections between seemingly unrelated subjects.