What is the sidebar in game analysis? - Chess Forums

I am watching game analysis and I wonder what is this sidebar that displays black and white color and some numbers? And why did it change so rapidly when black made this move?

Soldier Chess, Board Game

Centre Chess, Board Game

Stylus client-side customized screen for your Twitch or streams - Chess Forums

White to play and win : r/chess

Best chess analysis software - Chess Forums

Chess Analysis after Game • page 1/2 • General Chess Discussion •

Why can I only see the last 50 games on my archive? - Chess Forums

What is the sidebar in game analysis? - Chess Forums

Questions: re: Library's Saved Analysis collection vs. current Saved Analysis collection - Chess Forums

Chess pieces best place to buy or locate quality pieces . : r/chess

Sidebar doesn't work - Chess Forums