There are two main classifications of stress - acute and chronic. Acute stress is normal in modern life, and can be caused due to any information or event that gives rise to unpleasant feelings. Some stressors that cause acute but short-lived stress are events such as being caught in a traffic jam, watching an unpleasant movie, deadline-related work pressure, or even the absence of work. Chronic stress is caused due to a continued state of stress that refuses to go away.
Basically, stress is a matter of perception, and therefore the manner in which one thinks about things and events is one of the biggest causes of stress. A stressor does not cause stress on its own. It is the manner in which it is perceived that causes the stress. It is thus impossible to conclusively predict accurately for all what the largest causes of stress may be. For some people, financial troubles are far more stressing than relationship problems, while for others, an unhappy spouse can cause more stress than an impending deadline at work.
The most common causes of stress are believed to be financial, workplace-related, health issues, and domestic or relationship issues. But if we look deeply into each of these broad classifications, the basic cause in these too boils down to individual perceptions and the way one thinks. One individual may be too happy to have lots of spare time at work, while the other might complain about the same situation and fret about becoming redundant. Some people are stressed because they have too much to do, while others would look at it as an opportunity to show their abilities. Similarly, many people would rather limit their expenses or strive to excel and seek promotions rather than crib about their relatively lower compensation. Health issues are taken lightly by some, and others take it as a part of existence and try to manage it without feeling too stressed about it. But there are still others that take small recurring colds as likely threats to life and fret about the consequences of such problems.
The above really brings out the fact that almost everything has potential to cause stress, since it is the thinking that causes stress and not the event itself. The reality is that stress or a stress-free life is dependent upon how our brain interprets the data provided by our senses. "There is nothing either good or bad, but thinking makes it so." - Shakespeare
The fundamental truth is that we are all born equal, and inborn intelligences do not differ as much as many would like to believe. The fact is that we use only a miniscule percentage of our brain’s capabilities.
If a person experiences anxiety while constantly thinking about a stressor, the stress response of ‘fight or flight’ is liable to remain activated for longer period of time. This can lead to physiological and psychological disorders. Managing stress is the only option available for people who face such situations, because potentially stressful events are beyond your control. Shake away negativity and understand that it is easy to relieve stress if we really want to do so. A stress-free life is possible by developing a habit of looking at the positive side of events.