RTF is a cross-platform format for storing labeled text documents, created jointly by Microsoft and Adobe, as meta-tags for the format Word in 1982. Adobe has in 1985 continued to develop the format and created a language PostScript. The basis is a simple text format, control sequences which are not macros that are available for change, and teams with a fixed behavior.

HEIF is a container that can be a single image or a sequence of images which makes it ideal for Apple's Live Photos. It is based on HEVC (High Efficiency Video Coding). The format is more convenient than the old JPEG mostly because it is twice smaller despite the fact that is has excellent quality. Therefore you can storage more images on your Apple device which is great. HEIF was developed in 2013 by MPEG (Moving Picture Experts Group) but has become popular only when Apple decided to replace JPEG with it in 2017. However, not so many programs are able to open it which is why you might need to convert it to another format.