The visible matter that fills our solar system, and the astrophysical universe beyond, is largely found to be in the fourth state of matter -- plasma. These plasmas are almost always found to be both magnetized and turbulent. Understanding how plasma turbulence influences the flow of mass, momentum, and energy is critical to predicting the long-time evolution of many space and astrophysical systems. In this colloquium, I will outline our present understanding of plasma turbulence, highlighting its fundamental properties and identifying key unanswered questions at the forefront of the field. I will conclude by previewing what is to come in the next decade -- spacecraft missions, supercomputer simulations, and theoretical breakthroughs -- that may help us to develop the capability to predict the dynamics and energetics of plasma turbulence and its influence on the evolution of the heliosphere, our home in the universe.