What symbol is used to denote a register?

In assembly language and computer architecture, registers are often denoted by the symbol % or a specific prefix depending on the architecture. For example, in x86 assembly, registers are typically represented with a % symbol (e.g., %eax, %ebx), while in ARM assembly, they are usually referred to by their names without any prefix (e.g., r0, r1). In some assembly languages, registers may also be indicated by a specific letter or abbreviation.