What is the seasonal trend lowess model in time series?

I am trying to understand how the trend line is produced automatically from software I am using for time series (iNZight). A textbook I have says "a local weighted regression line is fitted to a window of points, so that values near the edge of the window are given less weight than observations near the center of the window when determining the local regression line".

I’m a bit confused. Is this the same as LOESS regression (shown at 2:27 https://www.youtube.com/watch?v=0ar9extHObg&t=155s )? In the description above it says that one line is added to a window of points, but in that video, there are numerous lines going through to create one line?