Moving Picture Experts Group (MPEG) developed HEIC as an upgrade to the popular JPG file format. HEIC originates from Apple’s initial HEIF (High-Efficiency Image File Format). The new file format has compatibility issues with some apps or devices, thus forcing people to opt from HEIC to JPG.
It takes time to adapt to new features, so it will take a while for HEIC to go mainstream. If you are using iOS 11 or a later version you must have noticed the new HEIC file format of the photos taken with your iPhone camera.