channel for explanation: 

CIVIL 3D - Local Extrema
It just so happened that in my environment for 20 years there is no one who knew Civil 3D better than me ( I really realize my level of knowledge and see hundreds of people on the Internet who greatly exceed my knowledge of Civil 3D, but here is how many jobs I did not change, I was the best in terms of Civil 3D and autocad. I was often approached for advice. And so, I created a channel where I share Life hack.
If I explained something to someone more than 2 times, this is an excuse to record a video for YouTube.