File format

A File format is the extension of a file, and can be used to associate it with default programs for viewing, running and otherwise accessing/using the file.

Definition

A file extension is a string of characters preceded by a dot (.) and appended to the end of a computer filename. It usually consists of three (or sometimes four) characters, whose purpose is to identify the file type.

Common Formats

Examples of common formats include:

Documents

.txt | .rtf | .doc | .xls | .ppt | .pdf 

for formats such as PlainText, RichText, Microsoft Office WORD & Star/Libre/OpenOffice, Microsoft Office & EXCEL Star/Libre/OpenOffice Calc and other spreadsheets, Microsoft Office POWERPOINT & Star/Libre/OpenOffice and other presentations, Adobe PDF presentations, reports and documents

Fonts

In order to access new typography within a given system, you could use any of the following:

.ttf | .tte | .otf | .eot | .woff

for formats such as TrueType Fonts, TrueType Font (for EUDC usage), OpenType Format, Embedded OpenType, Web Open Font Format

Images

.jpg | .png | .gif | .svg

for image files of Joint Photographic Experts Group, Graphics Interchange Format, Portable Network Graphics, and Scalable Vector Graphics types, respectively

Audio

.mp3 | .aac | .amr | .wav | .wma

for audio files of MPEG-1 Audio Layer 3, Advanced Audio Coding, Adaptive Multi-Rate audio codec, Waveform audio format, and Windows Media Audio types, respectively

Video

.vob | .avi | .wmv | .rm | .divx | .flv | .3gp | .3g2 | .mpg | .mpeg | .mp4 | .m4v | .mov | .ogg | .webm

for video files of DVD-Video Object, Audio Video Interleave, Windows Media Video, Real Media video format, Digital Video Express, Adobe Flash Video (VP6), Third Generation Partnership Project, Third Generation Partner Project 2nd generation, Moving Picture Expert Group (MPEG), MPEG, MPEG H.264, Moving Picture Expert Group-4 (MPEG-4) Part 14, QuickTime (Macintosh OSx) Video Clip, Ogg Vorbis, and WebM (VP8) Open Video project types, respectively

Application

.exe | .app | .o | ""

for application (program) runnable files such as Windows EXEcutable, Mac APPlication, and .o or "extensionless" launchable Linux application types, respectively

Application Code

.java | .c | .h | .cpp | .cs 

for programming languages like Java, C, C/C++ (header for import), C++, C-Sharp (C#) respectively

System Scripts

.sh | .bat

Shell and Batch script types (for Unix-based systems and Microsoft Windows) respectively

Server-side Code

.jsp | .do | .asp | .py | .php |  .pl | .cgi | .cfm

for dynamic server-side scripts of JavaServer Pages (JSP), Java Struts DynamicObject, Active Server Pages (ASP), Python, Hypertext PreProcessor (PHP), Practical Extraction and Report Language (PERL), Common Gateway Interface (CGI), and ColdFusion Markup (CFM) language types respectively

Web Sites/Applications

.html | .xhtml | .dhtml | .shtml | .chtml | .htm

for web pages of HyperText Markup Language (HTML), eXtensible HyperText Markup Language (xHTML), Dynamic HTML, Server Side Includes (SSI) as HTML, Compact-HTML, and Microsoft HTML types respectively

Styles

.css | .xsl | .xslt

for client-side Cascading StyleSheets (CSS), eXtensible Stylesheet Language (XSL) and eXtensible Stylesheet Language Transformation (XSLT)

Behaviors

.js | .jscript | .vbscript

JavaScript, jScript or VB script interaction/presentation types

Data Structure specifications

.ddl | .dtd | .xsd | .rdfs

Data Definition Language (usually used for SQL and DBMS), Document Type Definitions (DTD), XML Schemas, RDF Schemas

Raw Data

.csv | .sql | .xml | .json | .rdf

for CSV data, SQL data dumps or SQL schemas, XML data, JSON data, RDF triple-stores

Archives/Packages

.zip | .jar | .tar | .tgz | .rar 

for archived files such as ZIP archive, Java ARchive, TARball, TARball (using GZip), Rational And Reliable (also known as Roshal ARchive) types, respectively

Resources

• File Types: http://technet.microsoft.com/en-us/library/dd346736.aspx
• Anti-Word (.doc parser/reader/writer): http://www.winfield.demon.nl/

Tutorials

• Limit the types of files users can upload: http://www.codestore.net/store.nsf/unid/DOMM-4Q8H9E/
• File input (or “upload”) in HTML forms: http://www.cs.tut.fi/~jkorpela/forms/file.html
• HTML <input> accept Attribute: http://www.w3schools.com/TAGS/att_input_accept.asp

External Links

• Howto Compiling C program and creating executable file under Linux / UNIX / *BSD: http://www.cyberciti.biz/faq/compiling-c-program-and-creating-executable-file/
• Executable File Types - File extensions used for executable files: http://www.fileinfo.com/filetypes/executable
• Arc File Format: http://archive.org/web/researcher/ArcFileFormat.php

See Also

MIME-types