I'm starting to read more and more about the different features of razors, and not just about the sizes, grinds and widths etc.

Because of this, I'm wondering what kinds of steel is used for the different razors, and how they all compare to each other in how good of an edge they can get and keep.
From what I've been reading, some of the best types are:

. Tamahagane steel from Japan. Mostly used from NOS from several decades ago, and is more expensive than gold but more or less the same as other types of high-carbon steel.
. Toleda from Spain, but originally from Arabia. Used in the first two generations of Filarmonicas
. Damascus, which I've only seen in customs by Mr Williams, Zowada, Livi etc.
. Swedish steel - I haven't been able to find much information about these, other than that the more recent Iwasaki razors are made from this. I'm not sure if "swedish steel" is the name of this kind of steel, or an umbrella term to describe many different types, like how Toleda is a sub-category of Spanish steel.
. Sheffield steel - Same as above. I have an 1830s razor which is stamped with "For use. Warranted" which I've read was a mark that the razor was made from Cast steel developed by Robert Huntsmann of Sheffield, but I would be interested in knowing more about it if possible.
. I've also been reading about "India steel" which some have compared to Wootz/ damascus steel.

So I'm mainly looking for information about the different types of steel used in razor making, how they compare to each other, and what India, Sheffield, Solingen and Swedish steel actually mean. Are they umbrella terms or certain types?