User mode is the usual mode for the execution of ARM or Thumb programs, that is it is used for executing most application programs

Fast interrupt (FIQ) mode is used for handling fast interrupts

Interrupt (IRQ) mode is used for general-purpose interrupt handling

Supervisor mode is a protected mode for the operating system

Abort mode is entered after a data or instruction abort

System mode is a privileged user mode for the operating system

Undefined mode is entered when an undefined instruction exception occurs.