You might find taking tests stressful. Your hands get sweaty and you might get butterflies in your stomach. If something makes you anxious, it is stressful.
Stress is how your body reacts to difficult situations. Driving through heavy city traffic can be very stressful, leaving you exhausted afterward. Some people react to stressful situations by eating too much, others by not eating, or by losing sleep. If you find something stressful, relaxation techniques like deep breathing and stretching can help your body release some of the tension and clear your brain. Then you won't be so stressed out!