Hi @hassesthlm,
I’m afraid I’m not familiar with Simply Static, so I can’t comment on that plugin specifically.
However, I can describe the difference between a static site generator (like Simply Static), and a caching plugin (like WP Super Cache).
Caching plugins don’t change the way your site works. The first time a user visits any page on your site, a copy of its HTML is saved and served to the next visitors until the HTML needs to be regenerated.
Caching plugins (including WP Super Cache) can be configured to pre-generate all of the pages on your site, too – so that visitors to your site will almost always be served a quick pre-generated page.
On the other hand, site generators like Simply Static generate a whole copy of your site as a directory full of HTML files, which can be served to your users without running WordPress at all.
As a general rule, I would recommend caching for almost any WordPress site, as it can improve the performance without altering the way it works. Static pre-generation can work for some sites, but I would not recommend it for any site with e-commerce, user accounts, or dynamic content that relies on communicating with the server.
