Pattern languages are powerful things. Alexander says “each pattern is a rule which describes what you have to do to generate the entity which it defines.” In architecture, rules allow you to create an infinite variety of unique buildings, which can in turn be combined to make a larger entity such as a town. In graphic design, grid rules allow you to create an infinite variety of layouts, which can in turn be combined to make spreads and books and websites.

A language in its most basic form has two requirements. It needs to have:
1. a set of elements or symbols
2. a set a rules for combining the elements or symbols

In the case of architecture, the elements are the rooms and passageways. The rules describe how many rooms there are, what kind they are, what shape they are, the shape of doorways, etc. Combining rooms and hallways following the set rules will result in a house that follows code and is habitable. In the case of graphic design, the elements are the type and images and whatnot that need to be included. The rules are the gridlines and hierarchy of information. Placing the elements within the rules will hopefully result in a page layout that makes sense and looks good.

“The elements are patterns. There is a structure on the patterns, which describes how each pattern is itself a pattern of other smaller patterns.”

You have your page dimensions, then your margins and bleed lines, then more gridlines break the space down to modules with gutters between them, then the elements are placed inside those gridlines.

“The fact is that every work of building, large or small, humble or magnificent, modern or ancient, is made the same way.”

That page is combined into a spread, which can be combined into a book. Or perhaps that page is designed for the web, so it is linked to other pages, and all those pages make up a website.

In typography, rules define how letters look. There are existing rules in place that tell us that the letter a has to have certain features in order for us to distinguish it from the letter b. So when designing a font, you need to follow those rules otherwise no one will be able to read it. You make your own rules about the style of the lettering, the line weights, the presence or lack of serifs and how they’re shaped, ligatures, etc. When using type, there are also general rules about the distance between letters and words, and how that applies to legibility. When you place type in a document, you have to keep in mind the legibility but you still have a lot of leeway in terms of how to style the text. You make rules about what should be bold, what should be italic, what size the title should be, which fonts you will use, etc.

“And your creative power is entirely given by the power of these patterns. Your power to create a building is limited entirely by the rules you happen to have in your language now.”

It is important to create effective rules, and explore new rules and keep them in mind when you start a project, because “at the moment when a person is faced with an act of design, he does not have time to think about it from scratch.”

“It is only because a person has a pattern language in his mind, that he can be creative when he builds.”

Pattern languages are not restrictive, but instead allow more freedom to explore in the time you have to complete a project. If you already have guides set up, you can spend time playing around with how you lay out the elements on the page.