Open captions and closed captions are both used to provide text-based representations of spoken dialogue or audio content in videos, but they differ in their visibility and accessibility options.

Here's the difference between closed and open captions:

Open Captions

• Open captions, also known as "burned-in" or "hardcoded" captions, are permanently embedded in the video itself.
• They are visible to all viewers and cannot be turned off or disabled.
• Open captions are typically added during the video production process and become a permanent part of the visual content.
• They are useful when the video is intended for a wide audience, including individuals who are deaf or hard of hearing, or when the video will be played in noisy environments where audio may not be easily heard (e.g. a museum).

Closed Captions

• Closed captions are separate text tracks that can be turned on or off by the viewer.
• They are not visible by default but can be enabled through the video player's settings or options.
• Closed captions provide flexibility for viewers who may not need or want the captions.
• They are commonly used in broadcast television, streaming platforms, and online videos to cater to diverse audiences and comply with accessibility regulations.
• Closed captions can be generated in real-time using a live writer or automatic speech recognition (ASR) technology or added manually during post-production.

Both open and closed captions serve the purpose of making videos accessible to individuals who are deaf or hard of hearing, those who are learning a new language, or those who prefer to read the text alongside the audio.

The choice between open or closed captions depends on the specific requirements and preferences of the content creators and the target audience.