What’s the difference between subprocess Popen and call (how can I use them)?

I want to call an external program from Python. I have used both Popen() and call() to do that.

What’s the difference between the two?

My specific goal is to run the following command from Python. I am not sure how redirects work.

./my_script.sh > output

I read the documentation and it says that call() is a convenience function or a shortcut function. Do we lose any power by using call() instead of Popen()?