Usually they say the spectrum of a black body is continue and emits radiation at every frequency. But how to understand that. Is it really continue like a line or are there (small) intervals?

F.i. they emit at 700nm and also at 400nm and everything what is between, but also at 400,000001nm and 400,000002nm etc.? So is it really like a wave or line which implies a kind of infinity of wavelengths or is it more or less like discreet lengths although very close to each other? Or is it not really known because measuring is in a certain way always with discreet numbers (like 400,0001)?

When I think about it, it would always be at certain discreet numbers, as first the electrons from which the radiation comes only have a discreet value and second collisions between atoms/protons/electrons creats not at every length. But that is just my interpretation.

So what is the reallity of black body radiation?

Usually they say the spectrum of a black body is a continuum and emits radiation at every frequency. Is it really a continuum like a line or are there (small) intervals?

For example, can a body emit at 700nm and also at 400nm and everything in between, or at very small intervals like at 400.000001nm and 400.000002nm etc.? So is it really like a wave or line which implies a kind of infinity of wavelengths or is it more or less like discreet lengths although very close to each other? Or is it not really known because measuring is in a certain way always with discreet numbers (like 400.0001)?

As I understand it, it should always be at certain discreet numbers, firstly because the electrons from which the radiation comes only have a discreet values, and secondly because collisions between atoms/protons/electrons create energy at certain set wavelengths. But that is just my interpretation.

So what is the reality of black body radiation?