Usually your hypothesis comes before the experiment/data collection. It’s what you expect to happen given your previous knowledge of the subject.

A theory is knowledge that’s been gathered by a study and has been replicated by a separate study.

A theory is a well-supported and widely accepted explanation for a phenomenon. It has been thoroughly tested and is backed by a large body of evidence.

A hypothesis is an educated guess or prediction about the explanation of a phenomenon. It is a starting point for further investigation and testing, but it is not yet proven or widely accepted.

In simple terms, a theory is a well-established idea, while a hypothesis is a proposed idea that needs further testing.

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A hypothesis is literally just a detailed guess at something that is testable through science. You have to be able to point at some data when you make that guess, but it's still just a guess. "Some data" could just mean data from a single test. It has just as much detail as a theory, it just has not "stood the test of time" yet

A theory is what you get once you have a hypothesis that has been around a while and despite numerous attempts to disprove it, has not been disproven, yet has also not been proven. So much so to the point where science generally recognizes it as truth, as if it were fact, except that they keep it in the back of their mind (or at least they should) that it is not actually a proven fact.

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In scientific discussion:

A theory is a working model, backed by experimentation, of the way the universe works in some way or another. Some examples of theories you have probably interacted with (or at least know of) are Darwin's Theory of Evolution, Newton's Theory of Gravity, and Einstein's Theory of Relativity.

These all work to explain a phenomena to the best of our knowledge, but they do have their limitations. Newtonian mechanics, for instance, breaks down in cases of extreme speed or extreme gravity, and Relativity exists to deal with those cases - Relativity meanwhile breaks down at very small values, which is where Quantum Theory comes in to fill in the gaps.

A hypothesis is your educated guess as to the outcome of an experiment before you run it. A really oversimplified example is "if I drop this feather and this bowling ball from the same height at the same time, I hypothesize that the bowling ball will hit the ground first" - then you test that hypothesis by running an experiment, and see if the shape of your intuition is right. In that case it is, but if you were to say something like "I hypothesize that if I drop a bowling ball and a basket ball from the same height at the same time, the bowling ball will hit the ground first" and then tested it, you'd find that it wasn't true, or at least wasn't as true as you thought it might be.

The real culprit isn't weight/mass, but air resistance. If you take that ball and feather and put them into a sealed chamber that you then vacuum seal, then drop them, they will fall at the same rate.

Making the hypothesis helps to narrow down the possibility space of a weird phenomenon, and get to those theories that you want.

In science, a hypothesis is a proposed explanation for a phenomenon. That would be what you in everyday language likely call a theory.

A Scientific theory is to quote the beginning of https://en.wikipedia.org/wiki/Scientific_theory

>A scientific theory is an explanation of an aspect of the natural world and universe that has been repeatedly tested and corroborated in accordance with the scientific method, using accepted protocols of observation, measurement, and evaluation of results.

So in the 19th century, what caused diseases was not really known. That bacteria is what causes infection was not known, So you might have the hypothesis that bacteria is what caused the infection. After expiration and test like what https://en.wikipedia.org/wiki/Robert_Koch did that shows that bacteria it the cause of many diseases.

The result is what is called https://en.wikipedia.org/wiki/Germ_theory_of_disease that germs can cause diseases. It is not just bacteria and another living thing like fungi( for example mold), protists (for example amoebas) etc. It can alos be no loving thing like viruses, prions, viroids etc.

So everything about how germs cause disease is a theory. The hypothesis was the idea before it was tested and shown to match reality.

That do not mean that all diseases are because of germ, it can be your own cells that do not work as they should. Autoimmune disease is for example your own immune system attaching your own tissue.

Before that https://en.wikipedia.org/wiki/Miasma_theory obsolete medical theory, that bad air causes disease, so it was the smell that could cause it. It was proposed as early as 4th century BC by Hippocrates. If you look at https://en.wikipedia.org/wiki/Plague_doctor with masks with beaks that contain dried flowers, herbs, and other things to keep the smells away. It likely helped because it keep droplets with bacteria away just like the facemask that is used today but the smell was not the cause.

The name malaria if from Italia where "mal" is bad and "aria" is air, so the literary means bad air. It was believed that the smell in for example wetlands caused it, the real explanation is that is a parasite that is transferred by mosquitos. So it did not smell but the existence of mosquitos in some areas caused it.

So both are explanations of a phenomenon Miasma theory was believed in for centuries even if it was not correct. But getting rid of smells can also reduce exposure to germs, so in a way it worked but why it works was not correct.

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