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File extensions

Before learning file extensions, let’s first understand about the files.

What is a File?

A file is an object that stores data, information, and commands on a computer in the form of a document, picture, audio, video, and application.

What is a File extension?

A file extension is a suffix that is added at the end of a computer file to identify the file types. It usually contains two to four characters. A file extension separate from a file name using a dot (.) symbol.

Example: A file name demo.html has a file extension .html. In this example, .html indicates that demo.html is a web page.

Types of file extensions

There are hundreds of file extensions that we commonly used in different file formats. Some commonly used file extensions are listed below –

1. Audio file extensions

There are the following important audio file extension that we use in our audio files –

• .cda – CDA stands for Compact Disc Audio. It is also referred to as CD Audio Track. These file extensions are created by the Microsoft Windows CD driver.
• .mp3 – MP3 stands for MPEG Audio Layer 3. It is an audio file extension developed by the MPEG (Moving Picture Experts Group). Mp3 is one of the most commonly used audio file extensions.
• .aif – AIF stands for Audio Interchange File Format. This audio format is developed using the Audio Interchange File Format (AIFF). It is commonly used to store standard audio in Silicon Graphics and Macintosh applications.
• .wav – WAV stands for Wave Audio File. This file format is created by Microsoft and IBM to store audio data, sample rate, and bit rate in segments. This file format is larger than the other file formats such as MP3.
• .wma – WMA stands for Windows Media Audio File. This file format is developed by Microsoft and released in 1999. It is mainly used in online music.
• .mpa –It is used for MPEG 2 (Moving Picture Experts Group 2) audio files. It is generally used for very small audio files. To open the .mpa file, we need a suitable software BusinessMAP.

2. Text file extensions

A list of most commonly used text file extensions is given below –

• .doc – .doc file extension is used by Microsoft Word to save a variety of documents such as letters, resumes, and essays.
• .docx – .docx file extension is used by Microsoft Word to Open XML Document.

Note: Microsoft 2007 to till now, .docx file extension is used.

• .txt – .txt file extension is used for the Plain Text File. This file format is created for all word processing programs. It allows us to create a text-based document without using font style, formatting, and text colors.
• .wps – This file format is used by Microsoft Word Processor to contain text, images, clip arts, as well as tables.
• .msg – .msg file extension is used by the Microsoft Outlook Mail Message. This extension contains ASCII text, email fields such as date, sender, recipient, subject, message body, and contact information.
• .tif – TIF stands for Tagged Image File. It is a universal platform for different computers to store images with high-quality graphics, including colors, digital photos, multiple pages, and support for layers.

3. Executable file extensions

A list of most commonly used executable file extensions is given below –

• .apk – APK stands for Android Package Kit or Android Application Package. This file extension is used in the Android and Google’s mobile operating system to easily download android applications.
• .bin – bin is a compressed binary file that is used in various computer applications such as anti-virus programs, backup image files, and more. These files are commonly opened in text editors like Notepad, Notepad++, and more.
• .com -MS-DOS and Windows run .com file extension. This file extension is used to hold approx 64 Kb of data. To view and edit the content of the .com files, we use a text editor like Notepad.
• .exe – EXE stands for executable. It is a Windows Executable File. This file extension is used by Windows, MS-DOS, OpenVMS, and ReactOS to install and run the software application.
• .jar – JAR stands for Java Archive File. JAR is an open standard file format that is written in JAVA and used to handle audios, images, directories, as well as class files. To view or extract the .jar files, WinZip software is used.
• .gadget – This file format is related to Windows Sidebar. The gadget file extension is used to manage mini-application called “gadgets”.
• .bat – bat file extension is used for the Batch files that are commonly created in the Notepad. This file extension is used to execute commands with the Windows Command Prompt.
• .py – py is a Python file extension. This extension can be created in any text editor but requires a Python interpreter to read the file’s content. It can be run on various platforms, including Windows, Mac, Unix, and mobile operating systems.
• .wsf – WSF stands for Windows Script File. This file extension is used for Windows script files that contain source code for scripting languages.
• .app – App file extension is associated with Alphacam. .app files are run on the Mac OS X operating system. It contains various directories, such as Contents, Resources, and Frameworks. These directories contain various files to create the application.

4. Image File extensions

A list of most commonly used image file extensions is given below –

.ai – AI stands for Adobe Illustrator. This file format is developed by Adobe systems to create and store graphics. This file extension is used to make logos and print media.

.bmp – BMP file extension is also referred to as a bitmap image file. This file extension is largely used on the Windows platform to store bitmap digital images and two-dimensional digital images with monochrome as well as color.

.gif – GIF stands for Graphics Interchange Format. It uses the LZW data compression algorithm. This file format uses more than 256 colors to make the image more beautiful and attractive. Gif file format integrates with various apps, such as Twitter, Facebook, Whatsapp, and Facebook Messenger.

.jpeg or .jpg – JPEG stands for Joint Photographic Experts Group. This file format is used by digital cameras and other photo capturing devices to store digital images. Commonly, lossy data compression is used in the jpeg file extension to share images over the Internet.

.png – PNG stands for Portable Network Graphic. This file format is used to store digital photos, web graphics, and images that contain transparent backgrounds, bitmapped or raster images.

.ps – PS (PostScript) file extension is developed by Adobe systems in 1982. This file extension contains vector graphics, raster graphics, text, or a combination of all these on the same page. Text editors like Notepad and Notepad++ are used to view .ps file content.

.psd – PSD stands for Photoshop Document. It is a popular image extension used in Adobe PhotoShop to support multiple image layers. A PSD file is capable of holding 30,000 pixels.

.svg – Scalable Vector Graphics (SVG) file format is created by the World Wide Web Consortium (W3C). This file extension is used to display XML based two-dimensional vector graphics on the web. This format is supported by internet browsers like Google Chrome, Firefox, Internet Explorer (IE), and Opera.

5. Compressed file extensions

A list of most commonly used compressed file extensions is given below –

.7z – 7z is an open-source, free, and the most popular compression tool. It uses a higher compression ratio with strong AES-256 (256-bit) encryption. The advantage of the 7z file extension is that it helps us to easily share and download files from the internet.

.pkg – This file extension is commonly used in the Apple OS X operating system. pkg file extension helps software designers to create installer applications that are used to install Mac software applications on the user’s Hard drive.

.rar – Roshal Archive Compressed (RAR) file extension is created by WinRAR in the 1990s. This file format is used to store one or more files as well as folders in compressed form. Most of the users preferred the rar file extension because it provides a high compression ratio and high security using strong encryption.

.zip – zip is one of the most commonly used compressed file format. zip file format helps us to easily receive and share files or groups of files using email over the internet. This file format is introduced by Phil Katz in 1989. It can be used for various purposes, such as file compression, encryption, and more.

.deb – deb file extension mostly used in the Unix based operating system to install, remove, and manipulate Debian packages. Deb files contain two zipped files, one contains the installer information for the associated application and another file contains the actual data for the application being installed.

.arj – ARJ stands for Archived By Robert Jung. This file format is associated with Compressed Archive. It is used to support long filenames, file version management, data integrity protection, and multiple archives.

.rpm – RPM stands for Red Hat Package Manager. This file extension is mainly developed for the Red Hat Linux operating system to store installation packages on the Linux operating system.

6. Internet related file extensions

A list of most commonly used internet-related file extensions is given below –

.asp – ASP stands for Active Server Page. This file format contains scripts that are written in the VBScript or JavaScript, HTML codes, text, graphics, and XML content. ASP pages are generated by Microsoft Internet Information Services (IIS).

.htm and .html – HyperText Markup Language (HTML) file format is used to design a basic structure of a web page, including various html tags such as headings, paragraphs, lists, and hyperlinks. This web page is displayed in the web browser.

.css – CSS stands for Cascading Style Sheet. This file format is developed by World Wide Web Consortium (W3C). CSS file extension is used to define the size, color, font, border, padding, flex, and more to make our web page more attractive and good looking on the web browser.

.js – js stands for JavaScript. A js file extension contains a JavaScript code that is used to run client-side JavaScript code on a webpage. A JavaScript file includes functionality such as automatically open and closes the web browser window or tabs, form validation, create drop-down menus, update the date on the web page, and so on.

.jsp – jsp stands for Java Server Pages. It is used to deliver server-side content on a web page. In short, a jsp file contains server-generated web pages. A JSP file helps web developers to create dynamic web pages based on HTML, XML or other document formats.

.part – part refers to partially download files from the internet. This file extension is used by Mozilla Firefox and several other file transfer programs, such as Go! Zilla, eMule, and discontinued eDonkey programs.

.php – Php stands for Hypertext Preprocessor. This file extension helps us to process online forms, data, and information using a database like MySQL. It also allows us to develop a variety of web pages and internet applications.

7. Programming related file extensions

.c – c file extension is associated with C or C++ programming language to store the source code.

.cgi – CGI stands for Common Gateway Interface. CGI file extension is a script file that is written in the C or Perl programming languages. This file extension is commonly used to run basic web scripts to create dynamic web pages.

.class – .class file extension is associated with a java programming language. This file extension is used to hold byte codes that are executed when run by a JVM (Java Virtual Machine). We use the javac command to compile the .class file.

.cpp – .cpp file extension is used to hold the source code written in the C++ programming language.

.h – h file extension is referred to as a header file used in C or C++ programming language. This file extension contains variables, constants, and functions.

.java – java file extension is used in Java programming language. This file extension is developed by Sun Microsystems but is now maintained by Oracle.

.swift – Swift file extension is introduced by Apple with iOS 8 and OS X Yosemite. This file extension offers memory management, provide new initializers, define new nested types, and integrates with existing Cocoa frameworks.

.vb – vb file extension is developed by Microsoft and written in the Visual Basic language. This file extension is commonly associated with Visual Basic script files. A vb script file can be executed in Windows or Internet Explorer.

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