Psychiatric disorders, also known as mental disorders or mental illnesses, are a wide range of conditions that affect mood, thinking, and behavior. These include mood disorders (like depression and bipolar disorder), anxiety disorders, psychotic disorders (such as schizophrenia), personality disorders, and neurodevelopmental conditions like autism or ADHD. Each disorder has specific diagnostic criteria outlined in classification systems such as the DSM-5 (Diagnostic and Statistical Manual of Mental Disorders) or ICD-11 (International Classification of Diseases). 

Psychiatric disorders can be acute or chronic and may vary in severity from mild impairments to disabling conditions. While exact causes are multifactorial—including genetic vulnerability, biochemical imbalances, and psychosocial stressors—many are treatable through a combination of medication, psychotherapy, and lifestyle changes. Early diagnosis and intervention are essential for better outcomes. A growing emphasis is being placed on patient-centered care, functional recovery, and reducing stigma through education, mental health advocacy, and policy changes.