Dementia is a term used to describe a decline in cognitive function severe enough to interfere with daily life. It affects memory, thinking, language skills, problem-solving, and other cognitive abilities. There are several types of dementia, each with different causes and symptoms. Alzheimer's disease is the most common type, accounting for 70%-80% of cases. It is characterized by the buildup of amyloid plaques and tau tangles in the brain, leading to memory loss and cognitive decline. Vascular dementia is caused by reduced blood flow to the brain, often due to strokes or other blood vessel issues. Symptoms vary depending on the affected brain areas. Lewy body dementia involves abnormal protein deposits called Lewy bodies in nerve cells, affecting thinking, behavior, and movement. Frontotemporal dementia affects the frontal and temporal lobes, leading to changes in personality, behavior, and language. Mixed dementia occurs when a person has more than one type of dementia simultaneously, often a combination of Alzheimer's and vascular dementia. While most forms of dementia are progressive and incurable, treatments can help manage symptoms and improve quality of life. Lifestyle changes, medications, and supportive care are essential for managing dementia. Early diagnosis and intervention can make a significant difference in the lives of those affected and their caregivers.