Digital Materials are a way of designing and manufacturing. Rather than building large, monolithic, single-use components, we discretize the material into simple, repeating, functional bits. A discrete set of base elements are combined to form cellular lattices with bulk material properties. This lets us cheat: we can maximize the performance of our material by assembling high-performance sub-elements, and their reversibility maximizes the sustainability and post-life reusability of the product. With all of these discrete units, assembly becomes a chore, and automation becomes crucial. The structured nature of the lattice enables assembler robots to use the geometry of the lattice for locomotion and error-correction. Further, the structured nature of the discretized lattice lends itself to novel design and simulation tools that exploit functional representations of the geometry to open the design space to previously unthinkable regimes of simulation, topological design and manufacture path-planning.