Peer into the dark and mysterious world of Ruby internals, delve to the point that the basic String becomes a complex web of optimizations, flags and peculiarities. The starting point for String Theory is the observation that immutable strings are more performant than mutable ones, and 23 character stings are more performant than longer ones. The how and why of these idiosyncrasies is where our journey begins. We'll pull apart the Ruby VM to explore how String is implemented in C, to fully understand String Theory we'll need to journey into Ruby memory structures and ultimately to the garbage collector. Get your spelunking gear ready as we discover how the GC has evolved, once we emerge from the darkness you'll see Ruby in a whole new light.