If you’ve ever wondered what those .odt, .ods, or .odp files are all about – or if you’ve stumbled across them and weren’t sure what to do – this post is for you.

.odt: The Open Document Text File

Think of .odt as the open counterpart to .docx. It’s the default file format for LibreOffice Writer. You can use it for everything from a quick grocery list to a dissertation.

What’s great about .odt is that it’s built on open standards. That means anyone can build software to read or write it without jumping through legal hoops. It also means you’re not tied to one company’s ecosystem, which is increasingly important when you think about long-term access to your own data.

Yes, you can open .odt files in Word – and yes, the formatting usually holds up pretty well. Not perfect, but usable.

.ods: Spreadsheets Without Strings Attached

Spreadsheets aren’t just for accountants anymore. Whether you’re managing a budget, tracking tasks, or planning a trip, you’re probably using rows and columns for something. .ods is the ODF version of .xlsx, and it’s handled by tools like LibreOffice Calc.

If you’re used to Excel, Calc will feel familiar enough. Basic formulas, charts, conditional formatting – it’s all there. Advanced Excel users might bump into limits (especially with macros or highly specific plugins), but for everyday work, .ods gets the job done.

And again, it’s open. Your data isn’t buried in a proprietary format you need a subscription to access five years from now.

.odp: Presentations Without PowerPoint

Then there’s .odp, the ODF format for presentations. It works like PowerPoint’s .pptx. You’ve got slides. You’ve got transitions. You’ve got bullet points. Even if you’re trying to build the next TED Talk with embedded video and flashy animations, it’s more than enough.

LibreOffice Impress opens and edits .odp files easily, and you can usually open them in PowerPoint too, though some visual effects might not translate perfectly. For most professional or academic presentations, it’s a reliable option – especially when you don’t know what software will be available on the receiving end.

Other File Types in the ODF Family

ODF isn’t limited to just text, spreadsheets, and slides. There are a few lesser-known formats worth mentioning:

• .odg – for vector graphics and diagrams. Think flowcharts, not Photoshop.
• .odf – confusingly, this one’s for formulas (as in math), used by LibreOffice Math.
• Templates like .ott (text), .ots (spreadsheets), and .otp (presentations) make it easy to standardize layouts and branding across documents.

These formats are all part of the same ecosystem. They’re modular, open, and designed to work well together.

Why It Matters

It’s easy to dismiss file formats as a technical detail, but they shape who controls access to your work. When you rely only on proprietary formats, you’re tied to that company’s tools, updates, subscriptions and limitations. You’re …

A document format is a tool for sharing knowledge and, as such, should be as simple and accessible as possible in relation to the complexity of the document content itself. This remains true even when the format is based on an XML schema that is hidden from users when the document is displayed on screen.

Unfortunately, while an XML schema can be simple, it can also be unnecessarily complex, bloated, convoluted and difficult to implement without specific knowledge of its features. This is true even if the on-screen documents are identical. In this case, complexity is an intentional tactic used to lock users into a vendor, as is the case with the Microsoft 365 document format.

An XML schema comprises the structure, data types and rules of an XML document and is described in an XML Schema Definition (XSD) file. This tells the PC what to expect and checks that the data follows the rules. In theory, XML and XSD together form the basis of the concept of interoperability. However, in practice, an XML schema can be made so complex that it becomes a barrier rather than a bridge.

An “artificially complex” XML schema goes beyond the level of complexity needed to display even the most intricate content on screen. In fact, it is completely disconnected from the actual complexity of the content, to the extent that even a simple sentence such as “To be, or not to be, that is the question” becomes an inextricable sequence of tags that users cannot access.

This artificial complexity is characterised by a deeply nested tag structure with excessive abstraction, dozens or even hundreds of optional or overloaded elements, non-intuitive naming conventions, the widespread use of extension points and wildcards, the multiple import of namespaces and type hierarchies, and sparse or cryptic documentation.

In the case of the Microsoft 365 document format, the only characteristic not present is sparse or cryptic documentation, given that we are talking about a set of documents totalling over 8,000 pages. All the other characteristics are present to a greater or lesser extent, making life almost impossible for a developer trying to implement the schema.

To illustrate how this translates into a lock-in strategy, consider a railway system where the tracks are accessible to all, but the main train manufacturer imposes its own incredibly complicated control system. In theory, anyone could build a train compatible with the tracks, but the control system specifications are so convoluted that only the main train manufacturer can ultimately offer rail services.

The worst thing is that passengers don’t realise they are being held hostage by technical constraints that they cannot understand until ticket prices rise or the number of cities served declines. At this point, the main manufacturer can dictate its terms, which passengers are forced to accept.

This is very similar to what is happening in the world of information technology, where Microsoft is effectively forcing its customers to switch from Windows 10 to Windows 11 against their will …

LibreOffice 24.8 has now reached the end of life, so all users have to update their free office suite to the latest release

Berlin, 17 July 2025 – The Document Foundation announces the release of LibreOffice 25.2.5, the fifth maintenance release of the LibreOffice 25.2 family for Windows (Intel, AMD and ARM), macOS (Apple Silicon and Intel) and Linux OSs, available for download at www.libreoffice.org/download [1].

LibreOffice 24.8 has reached the end of life, which means that this release – which includes dozen of fixes and enhancements that further improve reliability, performance and interoperability – is suggested for production environments, and all users should update their installation as soon as possible.

LibreOffice 25.2.5 is based on the LibreOffice Technology, which enables the development of desktop, mobile and cloud versions – either from TDF or from the ecosystem – that fully support the two ISO standards for document formats: the open ODF or Open Document Format (ODT, ODS and ODP) and the closed and proprietary Microsoft OOXML (DOCX, XLSX and PPTX).

Products based on the LibreOffice Technology are available for all major desktop operating systems (Windows, macOS, Linux and ChromeOS), mobile platforms (Android and iOS) and the cloud.

For enterprise-class deployments, TDF recommends a LibreOffice Enterprise-optimized version from one of the ecosystem companies, with dedicated value-added features and other benefits such as SLAs and security patch backports for three to five years.

English manuals for LibreOffice 25.2 Writer, Calc, Impress, Draw and Math are available for download at books.libreoffice.org/en/. End users can get first-level technical support from volunteers on the user mailing lists and the Ask LibreOffice website: ask.libreoffice.org.

Downloading LibreOffice

All available versions of LibreOffice for the desktop can be downloaded from the same website: www.libreoffice.org/download/.

LibreOffice users, free software advocates and community members can support The Document Foundation and the LibreOffice project by making a donation: www.libreoffice.org/donate.

[1] Fixes in RC1: wiki.documentfoundation.org/Releases/25.2.5/RC1. Fixes in RC2: wiki.documentfoundation.org/Releases/25.2.5/RC2.

Good software needs good documentation. But how do we define “good” in this sense? And what does the future hold? Find out in episode 4 of the LibreOffice Podcast! (This episode is also available on PeerTube.)

When different systems, applications or organisations need to communicate with each other and actually understand what is being said, interoperability is key. It enables a hospital’s software to communicate with an insurance company, for example, or one vendor’s inventory system to synchronise with another’s logistics platform.

At the heart of many of these data exchanges is XML.

XML (Extensible Markup Language) may not be new or flashy, but it remains one of the most powerful tools for achieving reliable, structured interoperability across diverse platforms.

Why is interoperability so hard?

Systems are built using different programming languages, data models and communication protocols. Without a shared format or structure, exchanging data can result in a complex web of custom APIs, ad hoc conversions, and manual adjustments.

To get systems working together seamlessly, you need:

• A standardised structure for data.
• A way to validate that structure.
• A format that is language-agnostic and platform-neutral.

XML ticks all these boxes.

How XML enables interoperability

1. Self-describing structure

XML uses tags to clearly label data:

<customer>
   <name>Maria Ortega</name>
   <id>87234</id>
</customer>

This means that a receiving system doesn’t have to guess what each field means, as it is explicitly defined. This reduces the risk of misinterpretation and supports automated parsing.

2. Schema validation

Using XSD (XML Schema Definition) or DTD (Document Type Definition), you can define the rules that an XML document must adhere to, such as which elements are required, which data types are valid and what the structure must be.

This is critical for:

• verifying incoming data
• preventing malformed or incomplete exchanges
• ensuring consistency across multiple systems

3. Namespaces for avoiding collisions

XML namespaces prevent tag name conflicts when data from different sources is combined.

<doc xmlns:h=”http://www.w3.org/TR/html4/” xmlns:f=”http://www.w3schools.com/furniture”>
   <h:table>…</h:table>
   <f:table>…</f:table>
</doc>

Without namespaces, systems could misinterpret elements with the same name but different meanings.

4. Cross-platform compatibility

XML is plain text. Any system that can read a file can read it, whether it’s written in Java, .NET, Python or COBOL. This makes it ideal for long-term data exchange and integration between legacy and modern systems.

XML in real-world interoperability

Healthcare: HL7 CDA/FHIR

Hospitals, clinics, insurance providers and pharmacies rely on XML-based formats to exchange clinical records, billing data and prescriptions. HL7’s CDA (Clinical Document Architecture) is a strict XML schema that is used worldwide.

In government, XML is used for e-government forms and tax data.

Tax filings, business registrations and compliance documents are often submitted in XML format. This ensures consistent structure across various jurisdictions and software vendors.

Publishing: DITA and JATS

XML standards are used for modular content creation and journal publishing to allow interoperability between authors, editors, publishers, and archive systems, even if they are using different tools.

Finance: XBRL

XBRL (eXtensible Business Reporting Language) uses XML to standardise financial reports, enabling regulators, investors and analysts to automatically process and compare data from …

Following the example of the German state of Schleswig-Holstein, which is moving 30,000 PCs from Microsoft Office/365 to LibreOffice, the Danish Ministry of Digitalisation is doing the same.

Caroline Stage Olsen, the country’s Digitalisation Minister, plans to move half of the employees to LibreOffice over the summer, and if all goes as expected, the entire Ministry will be free from Microsoft Office/365 later in the year.

In a LinkedIn post, Olsen summarised the reasons for switching to LibreOffice:

We must never make ourselves so dependent on so few that we can no longer act freely. Because far too much public digital infrastructure is today tied up with very few foreign suppliers. This makes us vulnerable. Also financially.

That is why we are now testing in parallel at the Ministry of Digitization how it works in practice when we work with open source solutions. Several municipalities are doing the same.

Not because we think it’s easy – but because we know it’s necessary to lead the way if we want to create more competition and innovation – and reduce our dependence on the few.

We in the LibreOffice project welcome this move, and look forward to seeing more governments and organisations getting control of their digital sovereignty and using public money for public code.

In my last article, I mentioned XML several times, perhaps assuming that all users had a basic understanding of it. Rereading it, I realised that an introduction to XML was needed for non-technical users, those who use XML every day without realising it, when they open a document, check the weather, place or receive an order online, or issue a digital invoice. XML works silently behind the scenes.

But what exactly is XML and why should it matter to non-techies? I will try to explain it in simple terms.

XML stands for eXtensible Markup Language, a way of organising information in a format that is easy for both people and computers to understand, helping different applications communicate and exchange data using a common language. Put simply, XML is a digital container that clearly labels information.

For example, this is a shopping list in XML format:


<groceryList>
  <item>
    <name>Bread</name>
    <quantity>1 loaf</quantity>
  </item>
  <item>
    <name>Milk</name>
    <quantity>2 litres</quantity>
  </item>
</groceryList>


Labelling helps computers and software understand exactly what each piece of information means.

In a hyperconnected world like ours, where apps and systems share data, XML allows that data to move between very different systems, such as credit card management apps and online shops. Without a common language like XML, communication between these systems would be much more complicated and slower, or even impossible.

So, XML is integrated into most everyday activities, even though it is completely hidden from users:

• All documents created by all office suites use XML, in some cases to facilitate transparency and interoperability, and in other cases to create a hidden layer of complexity with the aim of preventing transparency and interoperability.
• All apps that provide weather forecasts obtain updates by reading XML data issued by weather agencies.
• Almost all e-commerce applications use XML to manage communication between the website, the payment system, the bank and the shipping service.
• All blogs and news sites use XML to automatically transmit new content to readers.

XML is clear and easy to read because it organises data in an orderly manner with labels that are understandable to both humans and computers; it is flexible, as it is not limited to a single type of information and can be customised for different scenarios, from cooking recipes to flight schedules; and it is compatible with all platforms.

To appreciate the value of XML, you don’t need to have a deep understanding of the language, just know that it exists and that – when used properly, as in the case of the ODF format – it has the potential to help users achieve and protect their digital sovereignty.

Of course, it is equally important to know that XML can be used in exactly the opposite way, as is the case with Microsoft 365’s OOXML format (and previously Office), to limit users’ digital sovereignty and perpetuate lock-in through artificial file complexity.

In summary, XML is a silent enabler that ensures that users’ apps, services and data all speak …

Here’s our summary of updates, events and activities in the LibreOffice project in the last four weeks – click the links to learn more…

• We started the month with Episode 3 of the LibreOffice Podcast – this time looking at Quality Assurance (QA) in Free and Open Source Software. Watch it below – or on PeerTube.

• Then we announced the winners in the Month of LibreOffice, May 2025, providing information on how to get sticker packs. We’ve been sending out stickers and merchandise in the last few weeks, with a bit more to come!

• On June 6, we announced LibreOffice 25.2.4, the fourth minor update to our latest stable branch. All users are recommended to upgrade.

• Next, we posted another section from The Document Foundation’s Annual Report, “LibreOffice for End User Privacy”.

• The end of Windows 10 is approaching, so it’s time to consider Linux and LibreOffice! That’s the message behind the “End of 10” campaign, which we’re supporting.

• In the middle of the month, we posted news about a new tutorial added to the wiki, showing how to create colour wheels with LibreOffice.

• Throughout June, we posted various articles about ODF, the Open Document Format used by LibreOffice (and supported in many other office suites): An Analysis of the adoption of the Open Document Format; Understanding ODF compliance and interoperability; and A technical dive into ODF.

• Then we reported back from an event: LibreOffice at the Linux Arena in Pordenone, Italy.

• Before LibreOffice there was OpenOffice, and before OpenOffice there was StarOffice. And how was StarOffice developed? We talked to Stefan Soyka, who worked on the suite in the early ’90s, and has some entertaining stories to tell

• New LibreOffice merchandise is here! We updated our Spreadshirt shop with new designs and many extra items. Buy something and support LibreOffice – some of the proceeds go back to the project!

• Registration is now open for the LibreOffice Conference 2025. Join us from 4 – 6 September in Budapest – we’ll have technical talks, workshops, social events and more…

• And finally, we announced the new LibreOffice 25.2 user guides – awesome work from the documentation team.

Keep in touch – follow us on Mastodon, X (formerly Twitter), Bluesky, Reddit and Facebook. Like what we do? Support our community with a donation – or join our community and help to make LibreOffice even better!