I know we talked about this via pm because my original answer didn't show up after I posted it, but I'm going to post what I sent you here.
So the difference between those two modules then? as far as I have found, there is only one. You can make custom HTML modules global but not custom HubL modules. I'm not sure why. Perhaps the Hubspot generated wrappers are different around these modules but not to the point that it matters.
You can use html, css, js, HubL and etc. in both module types. Only for some reason you can't make Custom HubL global. It's possible that they made both of these for template navigation reasons(?). I just find it easier to use the custom html module because of it's ability to go global if needed.
I know we talked about this via pm because my original answer didn't show up after I posted it, but I'm going to post what I sent you here.
So the difference between those two modules then? as far as I have found, there is only one. You can make custom HTML modules global but not custom HubL modules. I'm not sure why. Perhaps the Hubspot generated wrappers are different around these modules but not to the point that it matters.
You can use html, css, js, HubL and etc. in both module types. Only for some reason you can't make Custom HubL global. It's possible that they made both of these for template navigation reasons(?). I just find it easier to use the custom html module because of it's ability to go global if needed.
Html is used all of the web. You will not find a website that doesn't use at least a few lines of html while most use thousands. I doesn't matter where or how your website is built, it is using html. If you use a generator or drag and drop builder html is being output on the back end.
HTML and CSS are basic web languages. They are used every where there is web, easy to learn, and can't do much but structure and style for aesthetics.
HubL is HTML wrapping server side code. so it's a more advanced for of html with a server side language additive.
What HubL really is is html combined with jinja. Jinja is a templating language derived from python. When was learning HubL, several years ago before the docs were useful, I relyed on jinja docs to find what I needed. It's important to understand that HubL is Hubspots version of Jinja. It is trimmed down, limited, and cannot be backed up by python scripting. You are limited to whats in the HubL docs. but it is still very powerful.
Hubspot is smart because they branded their code, but every cms or other system that doesn't consist of static .html text pages uses a server side language. WordPress has it's on version of PhP, Joomla. Drupal, magento, and CMSMS too I believe. Just remember that HTML, CSS, and Javascript all operate on the front end and there really aren't alternative versions of these, just more complicated (or simple: scss, sass, jquery, etc.). If it is anything beyond these three then you are most likely dealing with some server side language as well. It will process on the server before any of the above code is processed by the browser.
