Schizophrenia is a mental disorder that affects a lot of people; it is believed that worldwide there are millions of patients that suffer because of it. According to some estimates, 1 percent of the world's population may be schizophrenic, and it seems that about half of all patients in psychiatric hospitals are diagnosed with schizophrenia.

It was seen that schizophrenia affects people of any age, race, sex, level of education, or social class. Usually patients are diagnosed in their late teens or early twenties, but it can occur anytime. We may also mention that it is rarely diagnosed in children, and there are more men than women that develop the condition.

Psychiatrists categorized schizophrenia in five subtypes: paranoid schizophrenia, disorganized schizophrenia, catatonic schizophrenia, undifferentiated schizophrenia and residual schizophrenia.

Patients with paranoid schizophrenia suffer from delusions and hallucinations, and although they have relatively normal emotions and cognitive functions compared to those who suffer other forms of schizophrenia, they are at a risk for violent or suicidal behavior.

We must mention that hallucinations often take the form of hearing imaginary voices, that come from a supernatural entity or unknown source. When delusions appear, the patient will believe, unrealistically, that someone wants to harm him.

In what concerns patients with disorganized schizophrenia, we must mention that they are dealing with confused, disorganized patterns of speech, thought, and behavior, they may act silly or withdraw from the world around them.

It is known that catatonic schizophrenia has as characteristics symptoms abnormal types of posture and movement. It was seen that patients who have this type of schizophrenia may repeat certain motions over and over again, may stand or walk in peculiar patterns, or become rigid and unmoving for long periods of time.

There exist patients that show some symptoms of schizophrenia, but those symptoms do not match in the categories described before. This kind of patients are having the so-called undifferentiated schizophrenia.

The fifth category is the one of the residual schizophrenia. It is known that the patients that fit in this category no longer display the most severe symptoms of the first three types of schizophrenia although they have had at least one schizophrenic episode.

We must remember that schizophrenia is a chronic, severe, and disabling brain disease, but research is gradually leading to new and safer medications, scientists are using many approaches in order to learn about schizophrenia, and it is very possible that the future will bring good news for those affected by this disease.