The 12-book Micropædia is one of the three parts of the 15th edition of Encyclopædia Britannica, and the other two being the one-book Propædia and the 17-book Macropædia. The name comes from the word "micro" and "encyclopaedia". Micro means small and so, the Micropaedia is a small encyclopedia. The Micropaedia has articles that are very short, the articles are found in small strips. It is the opposite of the Macropaedia, which has articles that are very long.
The Micropædia was introduced in 1974 with 10 books having 102,214 short articles, all of them are less than 750 words. In the 15th edition, many articles were put together, with about only 65,000 articles in 12 volumes. In general, the 750-word limit is still used and most articles are only 1-2 paragraphs; however, a few longer articles can be found in the 2007 Micropædia, such as the Internet ones, which takes up a full page.
With some exceptions, the 65,000 articles of the Micropædia have no bibliographies and no named contributors. It is supposed to be for fast-checking to know only the main things about the topic, and as a guide to the 700 longer articles of the Macropædia. People use it to know just a little, but the Macropaedia is used to know in detail.