Data files contain both data and information. Data files created when a user uses an application will generally contain information. Data files are manipulated by the user and by program files. A program file contains the instructions necessary to tell a computer how to perform a task. Program files contain only instructions, but are necessary for the computer to run or to accomplish a task.
Program files are executable and are often called executable files.
Programs contain the instructions to perform the task, but they do not contain the data necessary to do it. Thus, a program is often used with data files. Program files often create data files as they execute. When creating a file, a file naming convention is used so that a user can distinguish between the types of files. This convention is part of the directory structure used with files on storage media.