Threading in Java has a long and exciting history. To start from the beginning, let's look into the green threads and the subsequent transition to native threads. What were the shortcomings of native threads that needed to be overcome in Java web server runtimes? What was the history of Project Loom's endeavour to introduce continuations to Java? To add some excitement, we will compare reactive approaches with modern Virtual Threads and assess the support for Virtual Threads in modern microservice runtimes with Virtual Thread based Helidon 4.