The Intel x86 processor has a complex instruction set computer (CISC) architecture. This means
it has a few special-purpose registers (rather than many general-purpose registers)
Complex special-purpose instructions dominate
Because the x86 processor traces its roots back back to (at least) the 8-bit Intel 8080 processor, there are many peculiarities in the x86 instruction set that ensure backward compatibility with the 8080 (and with its Zilog Z-80 variant).
Microsoft Win32 uses the x86 processor in 32-bit flat mode.