system
Given the following post, respond as if you're commenting on Reddit:
human
What is the difference between the six types of quarks?

I know that there are 6 different types of quarks (up, down, charm, etc.) But what exactly is the difference between them? How was it determined which combinations make up protons, neutrons, and so on? On a side note, are they small enough to be considered on the Planck scale? By throwing h = E in Einstein's E=mc^2, m=2.281 x 10^-42kg for something with one quantum of energy, so are quarks small enough to be on that scale? (I'm sure I'm not making much sense, but if you get what I'm trying to ask, I'm curious about it)
gpt
There are three "generations" of increasing size, and in each generation there is a quark with 2/3 the charge of a proton and another with 1/3 the charge of an electron. The first generation is up/down, the second is strange/charm, the third is top/bottom.

Starting in the 1950s, more and more particles were being discovered and it was thought that these were fundamental, but by grouping them in terms of common properties like charge and spin it was deduced that all of them could be explained as being made up by a small number of constituent particles, which were termed quarks.

Quarks aren't really Planck scale; their interactions relevant over femtometers, which is much much larger than the Planck length, and their mass is much much smaller than the Planck mass.

Planck's constant has units of angular momentum, not energy, so you can't equate it to an energy to determine a mass.