[mediacapture-transform] What does sink mean? (#39)

krave1986 has just created a new issue for https://github.com/w3c/mediacapture-transform:

== What does sink mean? ==
I am lead to this repo from this article:
https://web.dev/mediastreamtrack-insertable-media-processing/

Word "sink" is mentioned mutiple times in the doc.
What does sink mean here?
Could you please give some examples?

Please view or discuss this issue at https://github.com/w3c/mediacapture-transform/issues/39 using your GitHub account


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