# Introduction

The articles in this section describe how to implement common use-cases related to text tracks, subtitles, closed captions and metadata. These use-cases can range from programmatically detecting new metadata, to side-loading subtitles.

The `textTrackRendering` feature flag, included by default makes THEOplayer capable of supporting

* subtitle and closed caption formats like WebVTT, CEA-608, DVB Subs and TTML;
* metadata formats like ID3, emsg, EventStream and `EXT-X-DATERANGE`.

The `textTrackRendering` feature exposes the TextTracks API. This API allows developers to programmatically switch between text tracks, detect events related to text tracks (e.g. new active cue) and more.

## Related articles

* [How to dynamically change the visible captions](https://optiview.dolby.com/docs/theoplayer/v10/how-to-guides/texttrack/how-to-dynamically-change-the-visible-captions.md)
* [How to programmatically detect text tracks](https://optiview.dolby.com/docs/theoplayer/v10/how-to-guides/texttrack/how-to-programmatically-detect-text-tracks.md)
* [How to programmatically detect text track changes](https://optiview.dolby.com/docs/theoplayer/v10/how-to-guides/texttrack/how-to-detect-text-track-changes.md)
* [How to programmatically enable or disable text tracks](https://optiview.dolby.com/docs/theoplayer/v10/how-to-guides/texttrack/how-to-programmatically-disable-text-tracks.md)
* [How to detect active text track cues](https://optiview.dolby.com/docs/theoplayer/v10/how-to-guides/texttrack/how-to-detect-active-text-track-cues.md)
* [How to insert subtitles](https://optiview.dolby.com/docs/theoplayer/v10/how-to-guides/texttrack/how-to-insert-subtitles.md)
* [How to implement preview thumbnails in THEOplayer](https://optiview.dolby.com/docs/theoplayer/v10/how-to-guides/texttrack/how-to-implement-preview-thumbnails.md)
* [How to track ID3 cues/tags](https://optiview.dolby.com/docs/theoplayer/v10/how-to-guides/texttrack/how-to-track-id3-cues-tags.md)