should the fan on the MacBook Pro 16 inch always run? Even at very low CPU activity?

I am new to MacBook Pro. I had some issues in setting up and the fan made lot of noise. I followed advise and reset SMC. Now everything is smooth.

I do notice however, that the fan is constantly on, albeit at lower speed, but still running, even when all apps are closed. use Safari, typing this message.

So I am wondering, is MacBook indeed set so that the fan is always on? and only the speed can vary?