Glossary

A versatile, open, royalty-free audio codec developed by the IETF. It excels at both voice and music compression, offering the best quality-per-bit ratio of any audio codec.

An Emacs major mode document format for note-taking, task management, and literate programming. Supports outlining, tables, code blocks, and export to HTML/PDF/LaTeX.

A modeling error that occurs when a machine learning model learns the training data too well, including its noise and outliers, resulting in poor performance on unseen data. Overfitting indicates the...

PKCS#12: a binary format for storing a certificate chain and private key in a single encrypted file. Used for importing/exporting certificates with their private keys.

Portable Archive Exchange: a POSIX standard archive format combining features of tar and cpio with extended header support.

Point Cloud Data: the file format used by the Point Cloud Library (PCL) for storing 3D point cloud data from LiDAR and depth sensors.

Pulse-Code Modulation: a method for digitally representing raw analog audio signals. It is the standard uncompressed audio format used in CDs, WAV files, and professional audio.

PiCture eXchange: an early bitmap image format originally developed for PC Paintbrush. It uses run-length encoding compression.

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.

PHP: Hypertext Preprocessor: a widely-used, open-source server-side scripting language especially suited for web development. PHP powers major platforms like WordPress, Laravel, and Drupal, and runs o...

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.

Public Key Infrastructure: a framework of policies, procedures, and technologies used to manage digital certificates and public-key encryption. PKI enables secure electronic communication by verifying...

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.

Post Office Protocol version 3: a protocol for retrieving email from a mail server that downloads messages to the local device and typically deletes them from the server. POP3 is simpler than IMAP but...