Since nobody else brought it up: One big item is non-blocking I/O. The idea of non-blocking is that you can manage thousands of network connections with only a

Since nobody else brought it up: One big item is non-blocking I/O. The idea of non-blocking is that you can manage thousands of network connections with only a handful of threads, because when you do thread-per-connection, you'll notice that your threads are mostly asleep in typical I/O heavy networked systems (like web-server/database stuff that most of us work on). You can do non-blocking in java now, but only with nasty callbacks and Futures and thread pools and such. In Go you get non-blocking "for free" so that it looks like blocking I/O but the runtime automatically suspends & resumes virtual threads as I/O buffers fill & drain. One of the big inspirations for Loom was Go jealousy. For all Go's faults, this is a really nice thing to have.