File format
The file format is the structure of a file that tells a program how to display its contents. For example, a Microsoft Word document saved in the .DOC file format is best viewed in Microsoft Word. Even if another program can open the file, it may not have all the features needed to display the document correctly.
Programs compatible with a file format can give an overview of a file but may not be able to display all the file features. Also, with some programs opening a file format that is not supported may give you garbage.
Common file formats
Below is a listing of common file formats you are most likely to encounter while working on a computer. Click any of the links below for more information about the type of file or the extension.
| File type | File extension |
|---|---|
| Text | .asc .doc .docx .rtf .msg, .pdf .txt .wpd .wps |
| Image | .bmp .eps .gif .jpg .pict .png .psd .tif |
| Sound | .aac .au .mid .mp3 .ra .snd .wma .wav |
| Video | .avi .mp4 .mpg .mov .wmv |
| Program | .bat .com .exe |
| Compressed | .arc .arj .gz .hqx .rar .sit .tar .z .zip |
| Web page | .htm and .html |
Can I save a file in a different file format?
Yes, if the program you're using supports the other file format you want to use. For example, in Microsoft Excel, if you have a spreadsheet you want to change to CSV (comma-separated values) format, you could choose the Save As option to save as a CSV.
However, if the program did not support the file format, it could not be used to save the file in a different format. If you need a different file format, you need a program capable of opening both types of files or a file converter to convert from one file format to another.
Changing the file extension of a file does not change its file format.