HEIC is a file extension that Apple uses for the HEIF image format, which are usually coded by HEVC codec (High Efficiency Video Compression). This format is great for Live Photos because it can contain an image sequence. The best part about it is that you can store twice as many pictures in the HEIC format as in JPEG in the same size and quality because it uses the next-generation file compression.

Since 2007, Microsoft began to use a file format docx, which is created by using the Office Open XML. The format is a zip-file containing the text in the form of XML, graphics and other data that can be translated into a sequence of bits using patent-protected binary formats. At first it was assumed that this format will replace the doc, but both formats are still used today.