Hi Hafsa, In standard English, your sentences don't need either "speaking" or "talking." I would express your conversation as below: - What is the video about? - It’s about a prank. You may add "talking" (not "speaking") if you change focus from the video to the people in the video, like the following: - What are they talking about in the video? - They're talking about a prank. In general, "talking" is preferred with "about." - O What are you talking about? - X What are you speaking about? I hope that helps answer your question. ^__^

I would say "talking" is better. Sounds more natural to my ear (native British English)