The French term for boredom, ennui, is sometimes used in English as well, at least since 1778. The term ennui was first used "as a French word in English;" in the 1660s and it was "nativized by 1758".[7] The term ennui comes "from French ennui, from Old French enui "annoyance" (13c.), [a] back-formation from enoiier, anuier.[7] "The German word for "boredom" expresses this: Langeweile, a compound made of lange "long" and Weile "while", which is in line with the common perception that when one is bored, time passes "tortuously" slowly.[8]
One more key element of boredom is control. Boredom often occurs when you have little control over your situation. Waiting rooms, lectures, and airline gates are all places where you have little control over your situation. Normally, we react to unpleasant situations by changing the situation. If you don’t like a book you are reading, for example, you close it and do something else. Boredom happens when you are unable to change the situation.  
In a learning environment, a common cause of boredom is lack of understanding; for instance, if one is not following or connecting to the material in a class or lecture, it will usually seem boring. However, the opposite can also be true; something that is too easily understood, simple or transparent, can also be boring. Boredom is often inversely related to learning, and in school it may be a sign that a student is not challenged enough, or too challenged. An activity that is predictable to the students is likely to bore them.[31]
Some individuals are more likely to be bored than others. People with a strong need for novelty, excitement, and variety are at risk of boredom. These sensation seekers (e.g., skydivers) are likely to find that the world moves too slowly. The need for external stimulation may explain why extroverts tend to be particularly prone to boredom. Novelty seeking and risk-taking is the way that these people self-medicate to cure their boredom. 
Flow is a state of total immersion in a task that is challenging yet closely matched to one’s abilities, akin to “being in the zone.” Flow occurs when a person’s skills match the level of challenge presented by the environment and when a task includes clear goals and immediate feedback. Tasks that are too easy are boring. In contrast, tasks that people perceive to be too difficult lead to anxiety.

Second, boredom typically occurs when people have trouble focusing their attention and they believe the reason for this difficulty is in the environment. When sitting in the airport, for example, there is probably a lot going on. There are people having conversations that you could listen to. You probably have something to read. There may be televisions showing the news. But, the stress of waiting for a delayed flight often makes it hard to concentrate, and so your mind jumps from one thing to another. You assume that this is caused by the environment, and so you feel boredom.
The French term for boredom, ennui, is sometimes used in English as well, at least since 1778. The term ennui was first used "as a French word in English;" in the 1660s and it was "nativized by 1758".[7] The term ennui comes "from French ennui, from Old French enui "annoyance" (13c.), [a] back-formation from enoiier, anuier.[7] "The German word for "boredom" expresses this: Langeweile, a compound made of lange "long" and Weile "while", which is in line with the common perception that when one is bored, time passes "tortuously" slowly.[8]
“When I have neither pleasure nor pain and have been breathing for a while the lukewarm insipid air of these so called good and tolerable days, I feel so bad in my childish soul that I smash my moldering lyre of thanksgiving in the face of the slumbering god of contentment and would rather feel the very devil burn in me than this warmth of a well-heated room. A wild longing for strong emotions and sensations seethes in me, a rage against this toneless, flat, normal and sterile life. I have a mad impulse to smash something, a warehouse, perhaps, or a cathedral, or myself, to commit outrages, to pull off the wigs of a few revered idols...”
If he can maintain his concentration, Goetz intends to continue his own research into understanding the nature of boredom. He wants to measure physiological signs of arousal, which could one day add a new component to wearable health trackers. He’s also interested in investigating whether specific boredom types correspond to different age levels and cultures. “There are many important questions to be answered related to the boredom types,” he says.
People who lack self-awareness are more prone to boredom. A bored individual is unable to articulate what it is that he or she desires or wants to do. They have trouble describing their feelings. An inability to know what will make one happy can lead to a more profound existential boredom. Not knowing what we are searching for means that we lack the capacity to choose appropriate goals for engagement with the world (Eastwood, 2012).
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