The Timed Text Working Group has published a Working Draft of TTML Profiles for Internet Media Subtitles and Captions 1.0.1 (IMSC1). This document specifies two profiles of TTML1: a text-only profile and an image-only profile. These profiles are intended to be used across subtitle and caption delivery applications worldwide, thereby simplifying interoperability, consistent rendering and conversion to other subtitling and captioning formats.