.doc and .exe and .pdf – oh my!

Continuing on with the explanation of computer terms, today we are looking at file types.
Every digital file has an extension, a 3 or 4-letter code after the name, separated with a ‘.’- as in ‘text.doc’.
These extensions indicate what kind of file it is and which program or app should be used to open it. This list only shows the most common ones, there are hundreds more, and you can look them up by
searching for ‘xxx file extension’ on the web.

The extension also defines the way the information is stored; remember ALL files, whether text or image or others are broken down into 0s and 1s, and there are different ways of converting what you see on the screen into these basic codes. That’s why there is rarely just one extension for each file type, every company or organisation tends to develop their own way of converting information into a digital format.

Here is a short list of the most common formats you might find on your computer

Text Documents	doc or docx, odt, pdf, rtf, txt
Images	bmp, gif, ico, jpeg, jpg, png, svg, tif, tiff
Audio (music or voice recording)	mp3, ogg, wav, wma
Video	avi, m4v, mov, mp4, mpg, mpeg, wmv
Spreadsheet	ods, xls, xlsm
Presentation (Powerpoint)	odp, pps, ppt
Database (Access etc)	csv, mdb, sql, xml
Compressed (used to decrease download size)	iso, rar, tar.gz, zip
Executable (programs, apps)	apk, com, exe, msi

Usually your device will know what to do with each type of file and will also display a small icon in front of the file name in your file manager that shows which app will be used is you open the file.