Almost every layout has axes, invisible guidelines along which the key elements — text blocks, headlines, illustrations — are arranged. These guidelines are the elements of the grid. A grid can be very primitive and, for a book with a simple structure, may merely to be the baselines and margins of the text. Or it can be very complex, since it will have to deal, say, with the variety of texts, headlines, photos, announcements and graphics that make up a newspaper. For a multi-column magazine, the grid may unexpectedly change the number of columns from section to section, or on a website extend or compress in response to the width of the browser.
The structural basis of a composition is not always visible to the inexpert eye, but a layout without a grid is unlikely: it is almost surely there.
