Recommended File Format

Archive

Optical Disc Archive

• 🆓📖 .iso ISO: An optical disc file system image file format.

Universal File System Archive

• 🆓📖 .7z 7Z: General archive and compression format with more function and better compression ratio than ZIP. But not many file formats use 7Z as the base format.

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• 🆓📖 .bz2 Bzip2: Single file compression format.
• 🆓📖 .gz Gzip: Single file compression format.
• 💰📕 .rar RAR: Archive and compression format.
• 🆓📖 .tar Tar: Archive file format. One advantage of this format is that Tar can save file permission information on file systems of Unix-like systems. But I personally think it’s better to include a shell script with the archive to set the file permissions. This eliminates the need to use a tar archive.
• 🆓📖 .xz XZ: Single file compression format.
• 🆓📖 .zip ZIP: General archive and compression format, also as the basis for many other file formats.

Audio Sampling

• 🆓📖 .aac AAC: Lossy audio sample format, but better than mp3.
• 🆓📖 .flac FLAC: Lossless audio sample format.
• 🆓📖 .mka Matroska Audio: Matroska audio. Used to encapsulate complex audio files or as components of other Matroska formats.

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• 🆓📖 .mp3 MP3: Lossy audio sample format.
• 🆓📖 .wav Waveform Audio File Format: An audio file format. It uses the linear pulse-code modulation (LPCM).

Bibliography Data

• 🆓📖 .bib BibTeX: A data format for recording citation sources.

Diagram Drawing

• 💰📕 .vsdx Visio XML Format: A diagram file format based on XML and ZIP.

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• 🆓📖 .odg OpenDocument Graphics: A vector image and diagram file format.
• 💰📕 .vsd Microsoft Office Visio Binary File Format: A diagram file format.

Document Typesetting Description

Common Document Typesetting Description

• 🆓📖 .md Markdown: A simple markup format used to write documents without complex style or structure.
• 🆓📖 .tex TeX: Markup language format for TeX typesetting system.

Web Page Style Sheet

• 🆓📖 .css Cascading Style Sheets: A markup language used to describe the styles of HTML elements.
• 🆓📖 .scss SCSS: A markup language that generates CSS. It’s like an extension to SCSS.

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• 🆓📖 .sass Sass: A markup language that generates CSS.It uses indentation to indicate code levels.

Web Page Typesetting

• 🆓📖 .html HyperText Markup Language: Markup language for Web typesetting.

E-document

Publish

• 🆓📖 .epub EPUB: E-book format based on web related technologies.
• 🆓📖 .pdf Portable Document Format: Mainly used as document format for both scanned and rendered, sometimes used as vector image format.

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• 🆓📕 .chm Microsoft Compiled HTML Help: Compiled HTML documents.
• 🆓📖 .djvu DjVu: Document format or pixel image format for scanned documents.

Editable Document Container

• 🆓📖 .docx Office Open XML Document: Editable document container for Microsoft Office Word etc.

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• 💰📖 .doc Microsoft Office Word Binary File Format: Editable document file format.
• 🆓📖 .odf OpenDocument Formula: A format to save math formula typesetting.
• 🆓📖 .odt OpenDocument Text: An editable document file container format.

Hardware and Operating System Level Programming

C Compiler Source Files

• 🆓📖 .c C Programming Language Source File: Source code file format of the C programming language.
• 🆓📖 .h C Programming Language Header File: Header file format of the C programming language.

C++ Compiler Source Files

• 🆓📖 .cpp C++ Programming Language Source File: Source code file format of the C++ programming language.
• 🆓📖 .hpp C++ Programming Language Header File: Header file format of the C++ programming language.

Rust Compiler Source Files

• 🆓📖 .rs Rust Programming Language Source File: Source code file format of the Rust programming language.

Pixel Image

• 🆓📖 .apng Animated PNG: Lossless animated pixel image format.
• 🆓📖 .jpg JPEG Format: Lossy pixel image format.
• 🆓📖 .png Portable Network Graphics: Lossless pixel image format.

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• 🆓📖 .gif Graphics Interchange Format: Lossless animated pixel image format.

Plain Text

Files without extensions will be treated as plain text files by default. But there is still a suffix for plain text files:

• 🆓📖 .txt Plain Text File: Basic text file format.

Presentation Document

Presentation documents are still documents consisting of text and images. But they can also contain audios, videos and animations.

• 🆓📖 .pptx Office Open XML Presentation: An interactive graphic file format.

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• 🆓📖 .odp OpenDocument Presentation: An interactive graphic file format.
• 💰📖 .ppt Microsoft Office PowerPoint Binary File Format: An interactive graphic file.

System Shell Script

Different shells are essentially different runtime environments, but are grouped together because they serve the same purpose.

Bash Environment

A type of shell script mainly used on Unix systems (including Bourne Shell). Overall the syntax is archaic and strange. Sometimes adding an extra space before or after an operator can cause errors.

• 🆓📖 .sh Bourne Shell: Universal system management script for Unix.
• 🆓📖 .profile Bourne Shell Config: The file used for the initial configuration of the Bourne Shell. It is also supported by many other shells.
• 🆓📖 .bashrc Bash Config: Script for setting up Bash.

PowerShell Runtime Environment

• 🆓📖 .ps1 PowerShell: PowerShell script file.
• 🆓📖 .psm1 PowerShell Module: PowerShell module file.
• 🆓📖 .psd1 PowerShell Manifest: Manifest for generate PowerShell Module.

Timed Text

• 🆓📖 .mks Matroska Subtitle: Matroska subtitle. Used to encapsulate complex subtitle files or as components of other Matroska formats.
• 🆓📖 .srt SubRip: A plain text-based external subtitle format.

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• 🆓📖 .lrc LRC: A simple lyric file format. Mainly for music.

Tabular Data

Tabular data does not necessarily need to be represented in a dedicated tabular file format. It is also possible to use the common markup data format like JSON or XML.

• 🆓📖 .xlsx Office Open XML Workbook: Spreadsheet file format, used for display tables or simple data tables, with some data processing functions.

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• 🆓📖 .csv Comma-Separated values: A simple markup language for representing tabular data. Use comma as delimiters. There are some variations of it. They are collectively called “Delimiter-seperated”. Delimiter-seperated values are not as good as binary files in terms of compression rate, and are not as good as XML, JSON, etc. in terms of scalability and data type richness.
• 🆓📖 .ods OpenDocument Spreadsheet: A spreadsheet file format.
• 🆓📖 .tsv Tab-Separated Values: A simple markup language for representing tabular data. Use horizontal tabs as delimiters.
• 💰📖 .xls Microsoft Office Excel Binary File Format: A data sheet file format.

Universal Markup Data

Although these file formats can theoretically replace each other, their different syntax designs cause them to have different adaptability to different scenarios. Generally, one or more of them are selected according to the needs or framework requirements. So there are multiple alternatives juxtaposed.

• 🆓📖 .json JavaScript Object Notation: A lightweight data markup language.
• 🆓📖 .toml Tom’s Obvious Minimal Language: A simple config file format.
• 🆓📖 .xml Extensible Markup Language: A common data representation format.
• 🆓📖 .yml YAML: An easy-to-read data file format.

Universal Runtime Environments

.NET Runtime Environment

• 🆓📖 .cs C# Programming Language Source File: Source code file format of the C# programming language.
• 🆓📖 .csproj C# Project Description File: The description file of C# project.
• 🆓📖 .fs F# Programming Language Source File: Source code file format of the F# programming language.
• 🆓📖 .fsproj F# Project Description File: The description file of F# project.
• 🆓📖 .sln Dotnet Solution File: The description file of dotnet solution.

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• 🆓📖 .vb Visual Basic Programming Language Source File: Source code file format of the Visual Basic programming language.
• 🆓📖 .vbprojVisual Basic Project Description File: The description file of Visual Basic project.

Python Runtime Environment

• 🆓📖 .py Python: A general programming language.

Vector Font

• 🆓📖 .otc PostScript-flavored OpenType Collection: Vector font collection file format. Mainly used for GUI operating systems.
• 🆓📖 .otf PostScript-flavored OpenType: Vector font file format. Mainly used for GUI operating systems.
• 🆓📖 .woff2 WOFF2: Vector font file for web.

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• 🆓📖 .ttc TrueType-flavored OpenType Collection: Vector font collection file format.
• 🆓📖 .ttf TrueType-flavored OpenType: Vector font file format.
• 🆓📖 .woff WOFF: Vector font file for web.

Vector Image

• 🆓📖 .svg Scalable Vector Graphics: Vector image format.

Video Container

• 🆓📖 .mkv Matroska Video: Matroska video. Used to encapsulate complex audiovisual files.
• 🆓📖 .mp4 MP4: A common audio and video container formats. Used to encapsulate relatively simple audio and video streams.
• 🆓📖 .ogg Ogg: An open source multimedia container. It’s also usually used as an audio format. It is worth mentioning that it is an open-source project - from file format to the official encoders.

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• 🆓📖 .avi Audio Video Interleave: An audio and video file format dominated by Microsoft.
• 🆓📖 .flv Flash Video: An audio and video container for Adobe Flash.