I'm sure this has been asked before, but I've looked around and can't figure it out:
How do I set a global maximum precision for a notebook (or in general, globally)?
I have a large notebook in which I'm trying to get Mathematica to do all computations to a precision of 15 digits. The objective is to compare the results of the computation at the end with the default precision to the 15 I am enforcing. What are the options that I have to set at the beginning of the notebook to make this happen?