There are all kinds of inventions that make modern living possible, but some fly under the radar.
Some so much so that we've only just figured out how they truly work.
Case in point: the washing machine.
Because apparently, no published paper was able to totally explain how these things got your clothes clean; not until 2018.
Now, to be clear, it's not like we had no idea how these machines worked.
The oldest washing machines that resemble our modern appliances date back to the 19th century, so these things have been around for quite a while.
And for years, we've had a really good understanding of how they use soap and detergent to get stuff off the surface of your clothes.
Soap is a surfactant, which is short for surface active agent.
That means its molecules can attach to two substances that don't normally interact, for example, oil and water.
Usually, one end of the molecule is hydrophobic, meaning it repels water, and the other end is hydrophilic and regularly bonds with water.
