File Types

RealAudio: a proprietary audio format developed by RealNetworks for streaming. It was pioneering in early internet audio streaming but is now largely obsolete.

Roshal Archive: a proprietary archive format created by Eugene Roshal. It offers higher compression ratios than ZIP and supports solid archives, recovery records, and multi-volume archives.

Raw Image Format: minimally processed data from a digital camera's image sensor. Each camera manufacturer has proprietary RAW formats (CR2, NEF, ARW, etc.).

Resource Description Framework: a W3C standard model for data interchange on the web using subject-predicate-object triples (Semantic Web).

RealMedia Variable Bitrate: a RealNetworks video format using variable bitrate encoding. Was popular in Asia for video distribution but is now largely obsolete.

ROOT Data File: the file format for CERN's ROOT framework used in high-energy physics for storing event data, histograms, and analysis objects.

RPM Package Manager: the package management format for Red Hat-based Linux distributions (Fedora, CentOS, RHEL).

XML-based web feed formats for syndicating frequently updated content (blogs, news, podcasts). RSS and Atom are the two major feed standards.

Rich Text Format: a document file format developed by Microsoft for cross-platform document interchange. It supports text formatting, images, and basic layout.

Source code for Racket, a general-purpose, multi-paradigm language descended from Scheme. Designed for language-oriented programming and used in education.

Source code for Raku (formerly Perl 6), a multi-paradigm language with powerful grammars, concurrency, and type system features.

A markup syntax for embedding C# code into web pages in ASP.NET. Razor uses the @ symbol to transition from HTML to C# and powers Razor Pages and MVC views in .NET.

A Python dependency file listing packages and versions for pip install. The traditional way to specify Python project dependencies.

The native file format of Autodesk Revit, a Building Information Modeling (BIM) software for architecture, structural engineering, and MEP. The industry standard for BIM workflows in construction.

Sorted String Table: the on-disk storage file format used by RocksDB, an embeddable persistent key-value store by Meta based on LevelDB.

ScreamTracker 3 Module: a tracker music format supporting 16-bit samples, up to 32 channels, and stereo panning.

SAS Dataset: the native data format for SAS (Statistical Analysis System), widely used in pharmaceutical, healthcare, and government data analysis.

Windows Screensaver: an executable file displayed as an animated screensaver when the computer is idle. Uses the same PE format as .exe files.

Syntactically Awesome Style Sheets: a CSS preprocessor that adds variables, nesting, mixins, inheritance, and functions. SCSS uses CSS-like syntax (.scss); Sass uses indented syntax (.sass).

The native file format for Trimble SketchUp, a 3D modeling tool popular in architecture, interior design, and landscape architecture.