o better define the subject, I'm not speaking here of using "free web art" pieces (on which I have already commented) or even using logical markup to bring out the structure of the document.  The "modules" I'm referring to are design elements you develop for using in a particular project---the specific headings, rules, buttons, and other paraphernalia united by the general style of the site, plus the abstract aspects of your composition: fonts, colors, textures, alignment styles, etc.

Thus, "modular design" is just another name for one of the most important design principles, consistency, which states that you should strive to minimize the inventory of different elements and materials used in any single composition.  This principle, despite being strictly negative (i.e. telling you what not to do), is immensely powerful and universally applicable.  By enforcing consistency and integrity, modular design makes your work not only easier but, more importantly, better.

This article discusses the theory and practice of modular design using the example of another site I recently designed, the "Books of Russia" online bookstore at http://books.ru.  My previous case study column, discussing the redesign of Quiotix Corp. web site, was well received by the audience, so I decided to present another "behind-the-scenes" article---which, rather than using the work of others for illustrations, indeed gives me a much better chance to thoroughly analyze both design fundamentals and minutia.

The "Books of Russia" site is in Russian, but since the article is devoted to design (as opposed to online book trade or Russian literature), this is unlikely to become an obstacle for those who don't read the language.  I will give you direct links to the pages being discussed (so you won't have to navigate the site yourself) and use pictures to point you to the relevant elements on each page.  In fact, this "pure" design example could be especially instructive because you won't be distracted by the text (in English design books, Latin text is often used with the same purpose).

As a sort of a theoretical introduction, the first part of this article discusses probably the most important principle in design---the principle of consistency.  Those impatient to see real-world design work can skip that section and go directly to the case study, traditionally starting with a logo design stage.  The next section, while describing the page layout and site-wide navigation system, introduces the main characters of our story---those colors, fonts, textures, and other style elements that are later grouped into modules and extensively reused on the front page's content area and the rest of the site.