Learn This: File Extensions and the Generation Gap

People of my generation (the author is in the late afternoon of his twenties) don’t get it.  What we don’t get is how relatively new and modern personal computing technology is.  We don’t realize that we were one of the first generations to have computers in our classrooms when we started kindergarten, one of the first to have internet access in our libraries, and one of the first to have networked computer interaction as a fundamental part of our lives from a young age.  We don’t understand why other generations don’t find computing as intuitive as we do.

Learning to use computers effectively is a process of repetition, immersion, and is ideally started early in life, just like learning a new language.  I think there is both a challenge and an opportunity – for all generations – in the generational computing gap.  The younger folks who can find ways to tailor their products and services towards usability, approachability and friendliness can often make big strides in taking new technologies mainstream.  Boomers and older have tremendous opportunities to separate themselves from their peers and their competitors by balancing a willingness to be open minded about embracing technology with a keen eye towards results.

In this spirit I would like to talk about a basic computing concept: file extensions.  First, what is a computer file?

A file is a block of information which can be used in conjunction with a computer program.  A file is durable in the sense that it remains available for programs to use after the current program has finished.  Computer files are the modern counterpart of paper documents which traditionally were kept in office files, which is the source of the term.

Every word processing document, spreadsheet, Microsoft PowerPoint presentation, MP3, and video on your computer is housed in its own “file”.  A program can use these files to achieve results, such as reading or editing a word processing document, using a spreadsheet to record and predict figures, showing a presentation at a meeting or conference, or to play a song or movie.

Each of these files has a name, and that file name usually has two parts. The actual name of the file, and then, after a period, or dot, a file extension.

For example, if you open your Microsoft Windows Notepad program in the acessories section of the start menu, click on the “File” menu, and then click “Save”, you’ll will be prompted to enter a name for the file, which is called “Untitled” until you name it. But you can also see that the file will be saved with the extension “.txt”.  If you choose to name the file “agenda”, the official name of the file will be “agenda.txt”.  In newer operating systems, you rarely actually see the file extension on the screen.  In Windows XP and Vista, you will see the file represented simply as “agenda” with a small icon next to it that looks like a sheet of paper from a small notepad – the symbol for the “Microsoft Notepad” program.

File extensions are less visible these days, but knowing how to interpret them can still pay big dividends.  The file extension serves to give the computer and its operating system a sense of how to handle the file.  By putting “.txt” after “agenda” in our Notepad document, we are notifying the computer what we intend to use the file for, which programs we want to use it with, and in general, what to expect when that file is opened. It’s no different than labeling a physical file in a physical filing cabinet. If all your invoices are in red files, you don’t have to look through the blue ones when searching for one.

File extensions are helpful in the same way to the user.  When we are emailed a file, or trying to download one, the file name and the file extension are important clues as to what the file contains. If my CPA emails me a Microsoft Excel spreadsheet file, I’ll know to look for the “.xls” extension.  If my lawyer sends me a contract, it very likely will come with the extension “.doc” for a Microsoft Word Document.  On the other hand, if someone says they are sending me a picture of a waterfall, and the program has a strange extension for an image, like “.dll” or “.exe”, than I know I’m going to want to be sure this is something I can trust. From here, the only thing to really learn is what the different file extensions are.

Common Microsoft Office / Document files

Common Multimedia Files

Other Common File Types