(The question comes with a picture of different medical machines;)
Human have designed simple machines to understand themselves and improve our health. Later, these machines have become more and more complex, complicated ones to extend human lives.
People built these simple machines for treatment such as suturing wounds, while the complicate machines can help us to look inside of our body.
These machines can scan and monitor brain activities, heart beats etc. E.g. ECG (electrocardiography).
