Cards mode provides a quick and simple way of providing a 'database' of articles, which can be searched by keyword. In reality, there is no database: the articles and index pages are all static, with the links calculated when the site is updated. This is very efficient for small numbers of articles, as the sorting process only happens once, but would become unmanagable for large numbers of articles. Possible applications include articles from a quartlerly newsletter, or fact sheets on a relatively small number of products.
All the articles are typed one after another into the body text box. Most formatted text commands are allowed, with the exception of tables. This is because the | character is used for a different purpose in cards mode.
Each article begins with a questionmark (think "search"), followed by a comma-separated list of keywords, followed by a | character. The rest of the paragraph is treated like any other paragraph, including any formatting characters such as =, > or 1+ which immediately follow the |. Subsequent paragraphs that do not begin with ? are treated as part of the same article.