If you want to publish the same content in more than one place on the website, but only wish to update it in one place, you can create a reference.
Go to the 'Special elements ' tab while creating a new content element and choose 'Insert record' (7.1)
In the 'General' tab you can see that the content element type 'Insert record' is selected (1).
You can add name (2) of a record, but it will be not visible in frontend. With the help of the buttons (3) you can access the page tree of the website, where you are then able to choose any page content (separate elements), news or pages.
NOTE! Selecting is easier if all content elements has a header. Content without header will be shown as 'No title' or with first frase of the text area, which can make it a little bit hard to find the correct content element.
Selected content elements will be shown in the field below (5) and they can be organised by using the arrows on the right hand side of the field (4), to move them up and down in the order or to remove a content from the selection (you need to mark it and use the necessary icon). (7.2)
Another way of creating references, and maybe a bit easier, is when you copy the element and then paste it with the paste icon, inside a 'Insert record' element. (7.3)
As a result, your reference will look a bit different than regular elements, and shown with a blue tint. (7.4)
But now all changes that are made in the original element, are mirrored in the reference.