3. File types

Commercial file formats

As you become familiar with various software applications you will begin to recognise common file formats.

For instance:

• .DOC : Word file
• .XLS : Excel spreadsheet file
• .PUB: Publisher desktop publisher file
• .PPT : PowerPoint file
• .MDB : Access database file
• .PSD : Photoshop file
• .SWF: Flash Player file
• .WMV : Windows Media Player file
• .PDF : Acrobat file

These formats have been created by commercial companies to support their particular application.

Originally the internal data formats of the files were private as only that company's application was intended to read and write to those files.

Public file formats

Then there are file formats that do not belong to any one in particular. For instance a .txt file can store very basic unformatted text data. It is very handy to transfer simple text from one application to another as all text processing applications can read a .txt file.

Another very common file format is the 'csv' file format, short for Comma Separated Values' where each chunk of data is separated by a comma or other 'delimiter'. This is widely used to import / export spreadsheet data