An electroencephalogram (EEG) is a non-invasive test used to record electrical activity in the brain. It involves placing electrodes on the scalp, which detect and measure the brain's electrical impulses. These impulses are then amplified and displayed as wave patterns on a monitor or recorded on paper. EEGs are valuable diagnostic tools in neurology, helping healthcare professionals evaluate brain function, diagnose various neurological conditions, and monitor changes in brain activity over time. They are commonly used to diagnose epilepsy, seizures, sleep disorders, and evaluate brain injuries or tumors. EEGs can also provide insights into brain development in infants and detect abnormalities in brain activity associated with certain psychiatric disorders. Overall, EEGs play a crucial role in understanding brain health and guiding treatment decisions for a wide range of neurological conditions.