What technologies are behind concurrent real-time multi-user web collaboration on documents?

I don't even know how to ask Google about it, don't know terms and names.

My questions are:

What is the name of the process when many users can edit the same web document simultaneously, and all other users can see in real-time how other user moves a cursor over the document or performs some actions over the elements of the document?

Examples are Figma.com, Google Docs, Google Sheets - people can collaborate on documents real-time and other people can see their actions on the document.

What is the name of current web technologies behind this this feature? Is it implemented with WebSockets?