Joomla module, where do these variables come from?

Question

PHP

I want to learn how to create modules for joomla, but the meaning of these variables is not clear to me, for example, the news module,

what are these variables and functions?
In Google I found partial information. Or I'm not catching up at all.
Friends point me in the right direction!

Answer 1

These are the module settings in the admin panel, obviously. The item is probably an array containing information about one news item. Why crawl into Google if you have all the code in front of your eyes?