To understand "margins" section if using a custom paper size

Question

In Pages, you can use custom paper sizes, e.g., 7.5 by 11 inches: File > Page Setup > Paper Size > Manage Custom Sizes.

Then there will be a window where you can set all the necessary values.

What I don't understand is the Margins section. I know what the margins are, but irrespective which values I set there, the document itself, after it has been created, ignores them, and I need to adjust margins again.

In other words, I try to understand whether (a) this setting simply doesn't work and this is a known bug or, instead, (b) I don't understand how it should work.

Answer 1

You are confusing Paper and Page, which are two different things.

When you create a custom Paper size, that defines the paper that a printer might use. The margins are to define the printable area, as some printers can't print all the way to the edges of the paper.

(Any printing devices that you have will be shown in the Margins: "User defined" drop-down menu, setting the margins to the pre-defined characteristics of those printers.)

By contrast, the Page margins of a document are simply an element of the design, rather than a physical attribute, and are usually unrelated.

The page size of a document is usually selected from a list of available paper sizes, but they are not the same thing.

You are right that a custom Paper size is available to every application. File > Page Setup was traditionally in every Mac app, and is more a part of the printing system and OS than just relevant to one app.