For many of us, troubleshooting begins and ends with the print statement. Others recruit the debugger, too. (Maybe you use print statements to look at changes over time but the debugger to focus on a small bit of code.) These tools are good, but they are the lowest level of how we can debug in Ruby. Letters leverages print, the debugger, control transfer, computer beeps, and other side-effects for more well-rounded visibility into code and state.