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A-Z glossary of PageSeeder concepts

PSML – PageSeeder Markup Language

PSML (PageSeeder Markup Language) is an XML markup language designed to represent a broad range of documents. It is natively supported by the components of the PageSeeder platform with no need for additional configuration. This includes the editor, publishing processes, validator, index/search engine and more.

PSML is also known as the Universal format. For developer information, see PSML element reference.


Because PageSeeder is designed to support arbitrary document structures, the language focuses on providing developers with familiar structural components. As a specialization of HTML, PSML recognizes that many of the objects designed for web pages are the logical descendants of objects that exist for non-web documents. With the right constraints, HTML structures like lists, images and tables provide a good foundation for a sophisticated publishing system. They have the added benefit of being understood by every computing device on earth.

Open standards exist for documentation, these include DITA , Docbook  and others. While they are considered, mature standards with plenty of support from their users and the development community, our feeling is that they demand too much of the markup language. This creates a situation where the standards are too complex to deliver on their fundamental objectives of portability, application independence and most importantly, productivity.

Instead of overloading the format that describes the content, PageSeeder moves some information into the application. Notionally, this makes the document less portable. In reality, our experience is that people care more about the immediate document production processes than the future exchange of documents.

Also, when standards become too complex, consistency between users and document collections is less likely. As a result, even moving documents between DITA systems might require the same amount of code needed to get from PSML to some flavor of DITA. In the meantime, because PSML is built on the infrastructure of the web, less code is needed to get started and become productive.

PSML has a number of ways to add and validate semantics to widely understood concepts of HTML. In particular, the use of linking extends HTML to support concepts from areas such the semantic web, the XLink standard and the classic hypertext concepts of Tel Nelson and Douglas Englebart

It is the powerful linking that allows PageSeeder to aggregate simple structures into comprehensive, sophisticated publications. By combining the document-neutral structure of PSML with XSLT, document formats such as PDF, DOCX or Lightweight DITA (lwDITA) are supported with no additional code.


PS XMLPrior to version 5.4, PageSeeder used a format known as PS XML that used what was known as the “Standard Schema”. This format is now deprecated
PSMLThe replacement for PS XML
xformatThe XML representation of the PageSeeder internal object model
standard formatThe deprecated XML-based representation of fragment content in standard documents
standard documentA PageSeeder document without a specific document type but with content that follows the Standard Schema
Universal format A zip package containing PSML and file system. Available in three variations:


The PSML format was introduced in version 5.2 of PageSeeder and could be created from PS XML using the <ps:export> Ant Task.

With PageSeeder 5.6, PSML became the default, native document format.

By PageSeeder 5.8, PSML was the only supported document format. The code to process PS XML is still available; anyone that needs help converting old documents should contact Allette Systems .

Created on , last edited on