Use captions for access and silent viewing
Captions show what is being said and help viewers who are watching without sound or who need written support. They are usually the first layer to add.
Use dubbing for another spoken-language audience
Dubbing replaces or adds the spoken track in another language. It works best when the translated script is reviewed for tone and timing.
Use voiceover to explain what the viewer sees
Voiceover adds narration, context or instruction. It can complement the original dialogue rather than translate it.
Combine them with restraint
A translated voice with captions can improve comprehension, but too much text and competing audio can overload a short clip. Give each layer a clear job.