Replicators

An electric kettle simmered in the background, and the boy donned mittens imitating a cat's paws to take a plate of hot sandwiches out of what looked like a small oven. But then he closed the door, and in a burst of light and sound another plate appeared inside. Then another. Might it have been a dumbwaiter? But no, it was clearly standing on little legs above the countertop. More impossible things.

— Distant Encounters

First there were 3D printers, able to create any shape on demand from a limited selection of materials. Then chemprinters, that could synthesize any substance out of the base chemical elements. Sooner or later, replicators were developed: machines that can break down nearly any matter into its component atoms and rearrange them at will.
In a single stroke, replicators revolutionized both the manufacturing of goods, and waste disposal. Most household goods could now be made only when needed, with zero manual work, and spaceships no longer had to worry about unexpected needs during long trips. Logistics became less of an issue for armies. Landfills became a thing of the past. Remote colonies could become self-sufficient with a smaller population and less available expertise.
Replicators aren't perfect. For one thing, they only go up to a certain size. Most commonly seen models are only as big as a microwave oven. Moreover, they can't replicate complex nanoscale structures such as DNA molecules. Worst, the replicator core -- the part doing the actual work -- can't be replicated itself. If it's damaged beyond its ability to self-repair, it takes specialized industrial machinery to make a new one. For these reasons, traditional manufacturing is still employed in parallel, and in some cultures people even avoid using replicators if they can help it.