Ask HN: What are the greatest scientific discoveries within the last 20 years?

[virjog]

What are the greatest scientific discoveries/accomplishments within the last 20 years that have propelled humanity (and our understanding of it) forward?

If necessary, can extend this to the past 50 years as well.

[mtmail]

A bit older but seem relevant "Ask HN: What are the greatest discoveries in the last few years?" https://news.ycombinator.com/item?id=9731111