Virtual Memory: "Page Table or Page Tables?" I am having a bit of a tough time grasping whether a computer system contains several page tables or just one page table. 

Some sources speak of page tables in plural others in singular. 

Intuitively it makes most sense to me that there is only one Page table containing all the physical addresses especially considered these addresses are to change over time. But I am not sure?
Each process has a different page table (since each process has a different address space). Each processor (or core if you want to be specific) can only have one active page table at a time, but the processor switches which table is used when it switches between processes.

I am also simplifying here because there are more tables used for IOMMU and hardware assisted virtualization.