Stage 1: Responsive/prompted. Child uses the toilet when taken or asked, but doesn't self-initiate. Has accidents if no one reminds them. This is often where training "clicks" first. Many parents call this trained; technically it's the beginning.
Stage 2: Daytime self-initiated pee. Child recognizes the urge and gets to the toilet independently for urination. May still have occasional accidents, especially when busy or distracted. This is what most Western parents mean when they say their child is trained.
Stage 3: Daytime pee and poop. Both pee and poop handled independently. This stage often lags — poop can come weeks or months after pee is sorted. Both completely normal.
Stage 4: Independent wiping. Child can wipe adequately without help. Typically not reliable until age 4–5 for poop. Many "trained" children still need help with this.
Stage 5: Nighttime trained. Reliably dry through the night without pull-ups. Bladder capacity sufficient to hold overnight doesn't develop until age 5–7 for many children. Nighttime training is a separate developmental process from daytime.