Nosocomial infections, also known as hospital-acquired infections, are infections that patients acquire while receiving treatment in a healthcare facility. These infections can occur in various settings, including hospitals, nursing homes, and rehabilitation centers. Common types include urinary tract infections, surgical site infections, and pneumonia, often caused by bacteria, viruses, or fungi. These infections can arise from various sources, such as contaminated medical equipment, improper hand hygiene, or close contact with infected patients. Preventing nosocomial infections is crucial for patient safety and involves practices like handwashing, using sterile techniques, and maintaining a clean environment in healthcare facilities.