How to delete all figure plots

I run a program with plot and histogram. Then the program generates plot windows. I would like to delete all these figure windows at the beginning of running the program next time. Please advise.

Answer 1

[Walter Roberson]

close all

[alpedhuez]

I typed clear all but the figure windows do not go away. (Windows 10)

[Walter Roberson]

"clear all" and "close all" are not the same.

In some cases you might even need

close all hidden