Microsoft Support
support.microsoft.com › en-us › windows › common-file-name-extensions-in-windows-da4a4430-8e76-89c5-59f7-1cdbbc75cb01
Common file name extensions in Windows | Microsoft Support
Windows file names have two parts separated by a period: first, the file name, and second, a three- or four-character extension that defines the file type. In expenses.xlsx, for example, the first part of the file name is expenses and the extension is xlsx.
Northwest Michigan University
it.nmu.edu › docs › common-windows-file-extensions
Common Windows file extensions | Technology Support Services
Windows file names have two parts; the file's name, then a period followed by the extension (suffix). The extension is a three- or four-letter abbreviation that signifies the file type. For example, in letter.docx the filename is letter and the extension is docx.
Videos
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What is a File Extension?
A file extension is a three or four-letter code that appears at the end of a filename and indicates the type of file it is. For example, .txt stands for text files, .jpg stands for image files and .docx stands for Microsoft Word documents. By knowing what kind of file, it is, your computer will be able to correctly open the file using the correct program.
lenovo.com
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File Extension: What is a File Extension? | Types of File Extensions?
What is the difference between a file name and File Extension?
The main difference between a file name and its extension is that while the filename identifies what type of file it is, the file extension provides more information such as which program should be used to open it. For example - a .docx file typically represents a Microsoft Word document, but without knowing the extension your computer will not know what program should be used to open it.
lenovo.com
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File Extension: What is a File Extension? | Types of File Extensions?
Why are there different types of File Extensions?
Different file extensions have been designed by software makers to help computers identify which program should be used to open them. This is because certain programs only work with specific file formats, so knowing the filename's extension can help you quickly figure out if you need to install another program in order to open the file.
lenovo.com
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File Extension: What is a File Extension? | Types of File Extensions?
Wikipedia
en.wikipedia.org › wiki › List_of_file_formats
List of file formats - Wikipedia
6 days ago - Most of the file endings are traditionally written lower case (example: .png) Each format is identified by a phrase that is the format's full or abbreviated name. The typical file name extension used for a format is included in parentheses if it differs from the identifier, ignoring case.
Archive and compressedComputer-aided extensionsDatabaseBig Data (Distributed)Desktop publishingDocumentFinancial recordsFont fileGeographic information systemGraphical information organizersGraphicsLinks and shortcutsMathematicalNative executablePage description languagePersonal information managerPresentationProject management softwareReference management softwareScientific data (data exchange)Source codeSecuritySignal data (non-audio)Sound and musicPlaylist formatsAudio editing and music productionRecorded television formatsSpreadsheetTabulated dataVideoVideo game dataVideo game storage mediaVirtual machinesWeb pageOtherGeneralized files
Client Portal
solutions.sierracollege.edu › TDClient › 1795 › Portal › KB › Article › 156645 › All-about-Files-extensions-types-convert
All about Files (extensions, types, convert)
For example, a Microsoft Word document (.doc, .docx, etc.) and an Adobe document (.pdf) are two different file types. While these file types are associated with individual applications, other file types, such as rich text (RTF) files and audio ...
suffix to the name of a computer file
Factsheet
Notation full stop
Notation full stop
Wikipedia
en.wikipedia.org › wiki › Filename_extension
Filename extension - Wikipedia
2 days ago - A filename extension, also known as file name extension or file extension, is a suffix to the name of a computer file (for example, .txt, .mp3, .exe) that indicates a characteristic of the file contents or its intended use.
ScienceDirect
sciencedirect.com › topics › engineering › file-extension
File Extension - an overview | ScienceDirect Topics
Many file extensions are commonly associated with ASCII files, although they are specified by application programs rather than by DOS itself. For example, .TXT and .DOC are common ASCII file types in DOS. In Windows, files with specific extensions are explicitly associated with particular applications: for example, .TXT files are usually associated with the text editor NOTEPAD.
Computer Hope
computerhope.com › jargon › f › fileext.htm
What Is a File Extension?
In the example above, the first file shown in Explorer is the "Regedit.exe" file. "Regedit" is the file name, and ".exe" is the file extension identifying this file as an executable file. The next file, "RtlExUpd.dll," is a DLL (Dynamic-Link Library) file and the last two are log files.
Indeed
indeed.com › career guide › career development › what is a file extension? a definitive guide (plus examples)
What Is a File Extension? A Definitive Guide (Plus Examples) | Indeed.com
October 4, 2022 - Regardless of whether your job directly requires IT-related knowledge and skills, learning about file extensions can help you gain a better understanding of the way most personal computers function.In this article, we discuss what a file extension is, explain what a hidden file extension is, provide examples of widely used file extensions and answer some frequently asked questions on the subject.
Lifewire
lifewire.com › what-is-a-file-extension-2625879
What Is a File Extension & Why Are They Important?
July 17, 2023 - The file extension helps an operating system, like Windows or macOS, determine which program on your computer the file is associated with. For example, the file notes.docx ends in docx, a file extension that's associated with Microsoft Word ...
Lenovo
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File Extension: What is a File Extension? | Types of File Extensions? | Lenovo US
A file extension is a three or four-letter code that appears at the end of a filename and indicates the type of file it is. For example, .txt stands for text files, .jpg stands for image files and .docx stands for Microsoft Word documents.
How-To Geek
howtogeek.com › home › windows › what is a file extension?
What Is A File Extension?
September 27, 2021 - File extensions are used by the operating system to identify what apps are associated with what file types---in other words, what app opens when you double-click the file. For example, a file named "awesome_picture.jpg" has the "jpg" file extension.
Apache OpenOffice
openoffice.org › dev_docs › source › file_extensions.html
List of File Extensions
This page lists the filename extensions, or suffixes, used in the source code.
educatecomputer
educatecomputer.com › home › software › 12 examples of file extensions
12 Examples of File Extensions - educatecomputer
February 17, 2026 - They help determine how the file behaves and which programs can open it. Common examples of file extensions include .docx, .pdf, .jpg, .xls, .pptx, and many more, which we look at below.
BleepingComputer
bleepingcomputer.com › home › tutorials & tech support guides › basic concepts tutorials › what is a file extension?
What is a File Extension?
July 17, 2012 - For example, the file extension.txt has an extension of .txt. This extension allows the operating system to know what type of file it is and what program to run when you double-click on it.
UC Browser
ucweb.com › blog › extension
What Is a File Extension? A Complete Guide & Examples
2 weeks ago - To better understand what is meant ... text, spreadsheets, and presentations. Common examples include `.docx` (Microsoft Word), `.pdf` (Portable Document Format), `.xlsx` (Microsoft Excel), and `.txt` (Plain Text)....
Study.com
study.com › business courses › business 104: information systems and computer applications
File Extensions and File Types: MP3, GIF, JPG, DOCX, XLSX, EXE, & More - Lesson | Study.com
October 24, 2013 - There are hundreds of file extensions - from .a to .z. And then there are special characters and numbers, too. Why so many? Some of this results from the fact that different files can contain very different data. For example, a .txt file contains text, while a .mus file contains music.
E 115
e115.engr.ncsu.edu › accessing-nfs › file-names-and-extensions
File Extensions – E 115: Introduction to Computing Environments
Some computers (primarily computers running Windows) may not always display the file extension to save screen space and make the file icons shorter and easier to read. Files can be named with extensions: for example, a file could be named funny.jpg, but not be a .jpg file.
Basics of Computer
basicscomp.com › home › file extensions list and their meanings
File Extensions List and Their Meanings - Basics of Computer
April 12, 2026 - This brings us to the end of the ... as there are many more file extensions in use. A file extension usually consists of three or more letters, though in some cases it may also be one or two letters. For example, .c, .go, or .py....
IONOS
ionos.com › digital guide › server › know-how › file extension overview
File extension list | The most important file types - IONOS
February 21, 2023 - The file extension can be used ... to open and edit the file. For example, a PDF file is a Portable Document Format file which can be opened with programs such as Adobe Reader....
FileCenter
filecenter.com › home › the giant list of document file types and extensions
The Giant List of Document File Types and Extensions
April 21, 2025 - Developers originally used filename extensions to indicate catalog or index information to other users such as TXT for plain text, MUS for music, and GFX for graphics. Over time, developers began writing programs with multimedia functionality capable of handling a variety of data types.