Cytotoxic T cells, also known as CD8+ T cells, are a type of white blood cell that play a crucial role in the immune system. They are responsible for identifying and destroying infected or cancerous cells in the body. When a virus infects a cell, it displays pieces of the virus on its surface. Cytotoxic T cells recognize these markers and spring into action to eliminate the threat. These cells are like the body's security guards, constantly patrolling for intruders. Once they find an infected cell, they release toxic substances that can kill the cell, preventing the spread of infection. This targeted attack helps keep the body healthy and free from disease.