Final answer:
An electrocardiogram (ECG or EKG) is a recording of the heart's electrical activity using electrodes placed on the body, providing essential details for diagnosing heart conditions.
Step-by-step explanation:
An electrocardiogram (ECG or EKG) is a vital medical tool used to record the voltages generated by the heart during its cycle of depolarization and repolarization.
These voltages are recorded by placing electrodes at specific locations on the patient's body. The instrument that generates an ECG can use various numbers of leads, with a 12-lead electrocardiograph being the standard, providing the most comprehensive view of the heart's electrical activity.
The data from an ECG can reveal detailed information about normal and abnormal heart functions, making it an indispensable tool for diagnosing heart-related ailments. Moreover, technological advancements have enabled the development of portable ECG monitors, such as the Holter monitor, which can record heart activity continuously for extended periods, typically 24 hours, while the patient goes about their daily routine.