Wolfram Mathworld says the following: "In fact, practically any function that can be described is measurable." (https://mathworld.wolfram.com/MeasurableFunction.html)
How accurate is this?
Note: I don't have much of a background in measure theory at all. I'm just trying to get a very basic understanding of what it means for a function be measurable since that is one of the conditions for a function to be Lebesgue integrable (and for Fubini's theorem to apply).