WHAT EVEN IS THAT?! Simply put, if you use something like OxyNinja, OxyMade or others with pre-defined classes, grids and all that fancy stuff. You my friend, are working with a framework. Now, if you're making sections with included classes, WINNER, all you need to do is go to the page, click the title, scroll down and click "shortcode", copy that and bam. Sorted. Then just submit your section and it's shortcode! It's important that you say WHICH framework it is, however. As mentioned before, without one, classes won't show up and elements will be broken.
Anything to do with classes and colours will not (unless it's changed, please feel free to correct me) carry over by default with shortcodes. So Hydrogen is required to copy your section/s. You can past Hydrogen section/s for FREE with the tool HERE.
How To Use Sections?
So, really simple. Head to the main directory, if you're using a framwork, be sure to use ones specific to that OR ones without one. Once you've done that, copy either the shortcode or hydrogen paste snippet. If it's shortcode, simply go to a page, click "Shortcodes" at the bottom and paste it! Though, making it a reusable may make it a little cleaner! If it's Hydrogen paste, simply hop in your builder and CTRL + V and you're done! Super easy, right?!