Both Ecg and Ekg refer to the same diagnostic test that records the electrical activity of the heart. They require similar certifications, are performed in similar healthcare settings, and are used interchangeably in the industry. The primary difference is the terminology preference in different regions, with 'Ecg' more common internationally and 'Ekg' used in the United States. Understanding that they are the same test helps job seekers and employers recognize the roles and qualifications associated with this position.