In a broad sense, crime is defined as any unlawful act, which is punishable by law. The scientific study of crime is known as 'criminology'. It involves studying various aspects of crime, including its nature, extent, and most important of all, its cause. In a broad sense, the cause of any crime can be psychological, biological, economic, or sociological.

Psychological Causes
Criminologists believe that certain predispositions and personality traits of an individual have a predominant role to play in his criminal behavior. These predispositions and traits rise from the occurrences in the surroundings and his tendency to relate to these occurrences. If Freudian psychologists are to be believed, the balance in the individual's id, ego, and super-ego is important for the person to live a normal life, and any imbalance in it can result in unruly behavior on his part. Basically, the person's super-ego is important as it brings about the positive behavior that is demonstrated by him. A weak super-ego and a strong id increases his chances of resorting to crime, as he is least concerned by the threat of punishment given by the society.

Biological Causes
When it comes to biological causes of criminal behavior, two factors come into play: genetics and neurological development. As far as genetic factors are concerned, a person's tendency to resort to crime is attributed to the traits passed on from his parents. Studies about criminal tendencies of people have found that those children whose parents have a history of crime are more likely to demonstrate criminal behavior as they grow up. In terms of neurological development, certain abnormalities and chemical imbalances in brain tend to make the person aggressive and prone to heinous criminal activities.

Economic Causes
As for economic factors, poverty is the first thing that comes to the mind. The desperation that comes with poverty eventually gives rise to anger and forces people to take extreme steps, thus making them get involved in criminal activities. In fact, studies about relationship between financial condition and criminal behavior show that economic deprivation is one of the key triggers of criminal behavior. An individual who is deprived of basic amenities, like food and shelter, is more likely to resort to crime to end this deprivation. That, however, doesn't mean that only those who are into poverty take to crime. If that was the case, the crime and poverty prevention measures implemented by the administration would have made the society crime free long ago. A large number of individuals take to crime to satiate their never-ending craving for money.

Sociological Causes
When we talk about challenges of urbanization, we can't ignore the changing lifestyle of people in urban areas and the role this 'change' has to play in their behavior. An individual's position in the society puts several limitations on him and he resorts to crime in a bid to adapt to these limitations. Other than the option of resorting to crime, the person also needs to have opportunities to learn how he can commit crime. This works on the basis of Edwin Sutherland's differential association theory, which states that a person learns the values, attitudes, and techniques required for criminal behavior on interacting with others.

While things are not very different in rural areas, the intensity of certain factors differs there. This difference can be attributed to the difference in urban and rural living. In rural areas, cultural factors have a much more dominant role to play as compared to other factors.