Stress is a condition of anxiety caused by an inability, or perceived inability, to cope with a situation.
It does not even have to be true only thought or assumed to be so.
Stress is the tension created by the difference between what is happening and what you want to happen.
Stress and pressure are not only terns to express your emotional feelings, these things are actually happening in your body. If you feel trapped in a traffic jam, in a relationship, or in a job, you feel an inability to successfully negotiate a change for the better in your life. Your heart works harder, your blood vessels become constricted, your body temperature rises and your breath more rapidly, but get less oxygen with each shallow breathe,
By calming the mind, you are creating a peaceful space within yourself so you can see how you are being.