File transfer is enabled in Group Chat unless you explicitly disable it for the chat room. In contrast, IM conversations only allow file transfer if you enable the functionality through the Management Center.
File transfer messages are cached when files are sent in IM conversations. A specific path can be specified in the management tool.
Files are uploaded and entered as message content, appearing in a similar format to URL links. A file can be uploaded and sent on its own, or you can enter other message content before and/or after it.
Files are formatted as a clickable regex that will download the file when clicked. Images and GIFs will render within the conversation with the file name clickable to open in a new tab. The image/gif can be downloaded File transfer allows users to send messages in IM conversations. This includes both images and text files.