Emotional stability describes one's general emotional state: To what extent you are resilient to setbacks, your tendency to experience strong emotions, and your propensity to worry.
People on one extreme are carefree, even-tempered, and composed, while people on the other extreme are heavy-hearted, hot-tempered, and anxious.
Optimism concerns how you deal with setbacks and failure. The scale goes from Heavy hearted to Carefree. People who are Heavy hearted are inclined to negative thoughts and emotions. People who are Carefree get past setbacks easily and stays optimistic.
Stability concerns how even and steady your temper is. The scale goes from Hot-tempered to Even-tempered. People who are Hot-tempered experience emotions intensively and get angry when provoked. People who are Even-tempered rarely get annoyed or upset.
Stress tolerance concerns how you experience stress. The scale goes from Anxious to Composed. People who are Anxious worry about things that have happened or might happen in the future. People who are Composed rarely experiences feelings of worry or stress.