An ECG, or electrocardiogram, is a medical test that records the electrical activity of the heart over a period of time. It uses small electrodes placed on the skin to detect electrical signals produced by heartbeats. The resulting graph helps doctors assess heart health, identify irregularities, and diagnose conditions such as arrhythmias or heart attacks. The ECG is a non-invasive procedure, meaning it does not require any surgery or insertion of instruments into the body. It typically takes only a few minutes and can provide valuable information about the heart's rhythm, size, and overall function, aiding in effective treatment planning.