TTML (Timed Text Markup Language) is an XML-based text format designed for representing timed text information. It's primarily used for subtitling and captioning in video and audio content. TTML files contain the text to be displayed, along with timing information that specifies when each piece of text should appear and disappear on the screen. This allows for precise synchronization of text with the audio and video content. TTML is a W3C recommendation and is widely supported by various media players, video editing software, and online video platforms. It provides a standardized way to represent subtitles and captions, ensuring compatibility across different systems and devices. TTML supports various styling options, including font size, color, position, and alignment, allowing for customization of the appearance of the subtitles or captions. It also supports multiple languages within a single file, making it suitable for multilingual content. The format is designed to be both human-readable and machine-processable, facilitating both manual creation and automated generation of timed text content. TTML is often used in broadcast television, online video streaming, and DVD/Blu-ray authoring.