What is a File?

A file is a computer resource for recording data, primarily identified by its file name, and usually having a file extension that identifies the type of file it is. Files can be documents, programs, or other types of data. For example: notepad.exe is an executable file; data.json would be a JSON file; logo.psd would be an Adobe Photoshop document.

HTML File Icon on Mac

A sampling of file types:

Text files
.txt, .html, .xml, .rtf
Server Side Scripting files
.php, .jsp, .asp
Web Image files
.gif, .jpg, .png, .svg, .webp
Audio files
.mp3, .ogg, .au
Video files
.mp4, .avi
Application files
.psd (Adobe Photoshop), .pdf (Adobe Portable Document File), .ai (Adobe Illustrator), .doc (Microsoft Word)