About IRS Tax Map

IRS Tax Map began in 2002 as a prototype to address the business need for improved access to tax law technical information by our telephone assistors. Tax Map is built on two concepts: semantic integration and the Topic Maps international standard (ISO/IEC 13250).

IRS Tax Map is a web presentation of an underlying "topic map", best understood as a kind of subject-oriented database — a database designed to organize information around subjects of interest to taxpayers. Each subject has a "topic page" in Tax Map. This page provides central access to everything that Tax Map knows about the subject. It may have links to the topic pages of related topics, as well as to relevant forms, instructions, publications and web pages.

IRS ceased publishing Tax Map in 2019 when the infrastructure of the programming used to publish Tax Map reached end of life. The Topic Maps standard that had guided the original creation of Tax Map, and Tax Map's deliberate emphasis on human editorial effort and responsibility, are currently not the focus of most available technologies. A suitable replacement system could not be found. Nevertheless, we believe that the human-intelligence-driven Topic Maps approach still has a place in the development of finding aids and research tools. Tax Map technology was based on the following principles:

  1. Every subject of conversation (or "topic" as it's called in Tax Map) is unique. When we talk about the depreciation of property, for example, we're presumably not discussing something else.

  2. A given subject of conversation may be independently identified by multiple identifiers. That is, any one subject can have any number of names, and any one of them will identify it as well as any other.

  3. A subject's names are not the subject itself; the names are merely handles for the subject. A subject's name allows us to tell others which subject we're talking about. The string "Statue of Liberty" is just a string; it is not a specific large statue made of iron and copper that stands in New York Harbor, or its smaller prototype in Paris, La Liberté éclairant le monde, nor is it the abstract notion of such a statue. It's a string, no more and no less; its significance, if any, is entirely in the mind of its reader.

    The distinction between names and subjects is easy for some people to grasp, and hard for others. Because we have the gift of language, our brains ignore the distinction between words and their meanings, and that lifelong habit can be a formidable obstacle to understanding the design philosophy of Tax Map. Even among media professionals, there are those who insist that an index entry is just a word or phrase, and that a search engine is just as good as an index. However, research shows that there can be considerable value in an expert-curated index, just as there can be considerable value in hiring an experienced guide when first attempting to climb a mountain. The primary purpose of an index is to help the user find information about some subject. Its purpose is not to help them find occurrences of some specific string.

  4. There is no such thing as a universal language, and there is no point in attempting to invent one. Inventing another language or vocabulary doesn't actually buy us anything but future maintenance problems. The focus of our thoughtful attention really needs to be on how real people actually talk about the things they talk about, and how other people will be assisted in finding what they need to know.

IRS Tax Map Archive IRS.gov Website