I'm learning about binary and am just curious about positional number systems. I get how they work but I'm just wondering if there is a convention of naming the positions like you might in computer science (e.g. the 'first' is actually the 'zeroth' - see pic related) or if this is just being used in the video as a placeholder for the exponents that you use for a given position later on.
https://www.youtube.com/watch?v=kTcpd4ef2lU

Is this the actual convention, or am I just reading too much into it?