If you ever need to tell someone you're not feeling well, or you have to go to the doctor, you can very clearly describe what is hurting or uncomfortable, so you are treated more quickly. For example, “mu pea valutab” means “my head hurts”. From there, you can replace “pea” (“head”) with any other body part word.
It can also be useful to know these words when playing sports and someone is describing a certain technique, telling you how to move a specific part of the body.
Watch Liisa Orav's video below where she teaches us body vocabulary, and their plural versions when applicable. Pause the video after each time she says a word so you can try to pronounce each like she does, and go back in the video if you need to try again:
