Ask HN: What important recent technologies is the median HN reader unaware of?

What are some important technological developments from the last 20 or so years that the median HN reader is likely not (fully) aware of? These may be world-changing technologies or more narrowly focused in scope. They may be well known within the relevant specialist community, but their existence or import hasn’t yet filtered into the broader public consciousness. For example, specific advancements in cutting edge media production techniques, software development tools or workflows, materials science breakthroughs, energy storage, transportation, etc.