You can convert a JFIF file to JPG, though the two formats are nearly identical, and most software will open a JFIF file as a JPG. On a Mac, you need to rename the JFIF file extensions to JPG and then ...
The widely used JPEG file format has lossy compression, which means that image data is lost when files are made smaller. The format was created in the 1990s; JPEG 2000, its successor, has JP2, JPX and ...