I was reading and came across the following paragraph
The X-rays thus produced by many electrons make up the continuous spectrum of Figure 2-10 and are very many discrete photons whose wavelengths vary from $\lambda_{min}$ to infinity.
So, I am wondering how can it range to Infinity, I mean isn't the range of wavelengths that we call X-rays from 0.01nm to 10 nm?
Breaking up the electromagnetic spectrum into discrete bins (x-rays, microwaves, radio waves, ...) is a tool which makes thinking about electromagnetic radiation easier. Putting hard limits on what you call an x-ray (e.g. $\lambda = 9$ nm is an x-ray, but $\lambda = 11$ nm isn't) is a pointless exercise - you should think about the categories more loosely than that.
In this passage, the author means that the process (Bremsstrahlung?) in question emits electromagnetic radiation which is primarily in the x-ray range, but in principle consists of all wavelengths above some $\lambda_{min}$. I think their passage gets the point across.
