OPML File – What is .opml file and how to open it?

OPML File: Definition and Structure

An OPML (Outline Processor Markup Language) file is a hierarchical data format designed to represent outlines and hierarchies. Developed by The Omni Group, it uses XML (Extensible Markup Language) syntax to organize and structure information in a tree-like format. The .opml file extension denotes files created in this format.

OPML files consist of a series of nested elements, each representing a node in the outline. Nodes can contain text, links, notes, or other data. They can also have child nodes, forming a hierarchical structure. The root node is the topmost element in the outline, and all other nodes are considered its descendants. OPML files provide a versatile method for organizing and managing information, including outlines, podcasts, RSS feeds, and other data structures.

Opening OPML Files: Software Compatibility

OPML files can be opened and viewed using a variety of software applications, particularly those designed for note-taking, outlining, and knowledge organization. Some popular options include OmniOutliner (macOS and iOS), Freemind (cross-platform), and XMind (Windows, macOS, and Linux). These applications provide comprehensive tools for creating, editing, and managing outline structures, making them ideal for handling OPML files. Additionally, web browsers such as Google Chrome, Microsoft Edge, and Safari can display OPML files in a tree view format, allowing for quick and easy navigation of the outline’s contents.

Converting and Importing OPML Files

In certain cases, it may be necessary to convert OPML files into different formats for compatibility with specific applications or devices. For instance, if you wish to import an OPML file into Microsoft OneNote, you can use the third-party tool “OPML to OneNote” to convert the file into the necessary OneNote format. Similarly, if you want to import an OPML file into a mind mapping software like MindMeister, you can use the “Import from OPML” feature within the application. These conversion and import options ensure that OPML files can be integrated and utilized within a wide range of software environments, facilitating the seamless exchange and sharing of outline data.

OPML File Structure

The OPML file structure adheres to the Outline Processor Markup Language (OPML) specification, defined by the Omni Group. It is an XML-based format that allows for the representation of hierarchical outlines. An OPML file typically contains a root element, which represents the outline itself, and a nested tree of <outline> elements representing the nodes in the outline. Each <outline> element can have attributes like text (the text content of the node), title (a human-readable title), and xmlUrl (a link to an associated XML document). Additionally, OPML files can include optional metadata, such as the outline’s title, date created, and author.

Applications of OPML Files

OPML files are primarily used for storing and managing outlines. They are commonly employed in applications like RSS readers, news aggregators, and mind mapping software. In RSS readers, OPML files enable users to organize and group their subscribed feeds, allowing for easy access and management. News aggregators utilize OPML files to create custom news feeds by combining content from multiple sources. Mind mapping software employs OPML files as a structured way to organize and visualize ideas and concepts. The flexibility and accessibility of OPML files make them a versatile data format for a wide range of applications.

Other Extensions