Xpub, Zpub, Ypub difference and multisig

I am setting up a 3 of 5 multisig wallet on Specter.

When I examine each of my device 's information, I am seeing something like this:

Multisig Sig (Nested)
m/48h/0h/0h/1h
[fingerprint]
Ypub****

When I examine my single sig wallets, I see this:

Single Sig (Nested)
m/49h/0h/0h
[fingerprint]
Ypub****

A few questions:

• I understand that m/49h/0/0 or m/84/0/0/ refer to the BIP version (44, 49, 84). Why am I seeing that my multisig paths have m/48? Is that a different BIP version?

• What is the difference between xpub, zpub and ypub? I assume that x/y/z are the same thing, but that different BIP versions yield either x/y/z? If so, why not just keep it xpub?

• When I export out my multisig details, Specter software offers an xpub, rather than z or y? Why is this the case?

• Ultimately, I am trying to understand the difference between x/y/z public addresses.

• Finally, what does the h represent in derivation paths?