File Types

Protein Data Bank: a file format for 3D structural data of biological macromolecules (proteins, nucleic acids). Standard in structural biology and drug design.

Portable Document Format: a file format developed by Adobe to present documents consistently across all platforms. It preserves fonts, images, and layout regardless of the viewing device.

Privacy Enhanced Mail: a Base64-encoded format for storing cryptographic keys, certificates, and certificate chains. Widely used in SSL/TLS and PKI.

Presentation Graphic Stream: a bitmap subtitle format used in Blu-ray discs. Subtitles are rendered as images rather than text.

XML configuration file for PHPUnit, the standard testing framework for PHP. Defines test suites, bootstrap files, and code coverage settings.

Process ID File: a file containing the process identifier of a running daemon or service. Used to manage and monitor server processes.

Playlist File: an INI-style multimedia playlist format used by Winamp and SHOUTcast for internet radio streams.

Polygon File Format (Stanford Triangle Format): stores 3D data from 3D scanners including vertex colors and normals. Used in 3D scanning and point cloud data.

Portable Network Graphics: a lossless image format supporting transparency (alpha channel). Created as a free, open-source replacement for GIF.

Netpbm formats: simple, uncompressed image file formats (Portable Pixmap, Graymap, Bitmap) used as intermediate formats in image processing pipelines.

Microsoft PowerPoint Binary File Format: the legacy presentation format used by Microsoft PowerPoint prior to the introduction of PPTX.

Office Open XML Presentation: the default presentation format for Microsoft PowerPoint since 2007. It supports slides, animations, transitions, embedded media, and speaker notes.

Adobe Photoshop Document: the native file format for Adobe Photoshop, supporting layers, masks, transparency, color profiles, and non-destructive editing.

Personal Storage Table: a Microsoft Outlook data file storing copies of emails, calendar events, contacts, and tasks for backup and archiving.

Python Compiled Bytecode: a compiled version of Python source code executed by the Python virtual machine for faster loading.

Apple Pages Document: the native word processing format for Apple's Pages application, part of the iWork suite. It is a ZIP-based package format.

A geometric modeling kernel by Siemens. Its exchange formats (.x_t text, .x_b binary) are widely used for CAD data interchange.

Apache Parquet: an open-source columnar storage format optimized for analytics workloads. It provides efficient compression and encoding for big data processing with Spark, Hive, and similar tools.

A text file containing differences between two versions of a file or set of files. Used to distribute code changes and fixes via email or issue trackers.

Python's native serialization format for converting objects to byte streams. Used to save ML models, data structures, and intermediate computation results.