I recently received an e-mail with a picture from an 80-year-old relative. I am very proud that she can learn to use a computer at her age. Unfortunately, I cannot read the file and I am reluctant to ask her to go through the process again. I know it is a picture, but the file ends with the extension 'php'. I thought that was used for programming or something. I have been unable to read the file or view the picture. She said she scanned it and sent it. Does that help? TrevorMid-Levels File extensions are wonderful things when they work. With the exception of Mac OS 9 and below, however, most of the time they do not behave properly. With the original MS-Dos operating system, file extensions were restricted to three letters and they had strict meanings. Anything that ended in 'com' or 'exe' was 'an executable' or what we today would call an application or program. It gave you a false sense of control, however, because the extension had no real influence or meaning. It was meant as a hint to help you remember what something was supposed to be. When Apple brought out the Macintosh in 1984, it changed things quite radically. It allowed for two 'forks' in a file, one for the data and the other for what it called the 'resource'. The resource fork actually tied the file to a particular application and you could double-click on it and it would launch the correct application. With DOS and later Windows, this was not possible. Unfortunately, Apple's great idea had to be abandoned because it was non standard. With its new OS, Mac OS X, the two forks have disappeared. Both the latest Windows OS and the Mac OS will handle file extensions reasonably well if it is a file you have created on your own machine. If it is something you got from the Web or, as in this case, something sent to you, things get more problematical. Both systems are likely to bring up a menu and ask you what application should open the file. This is not a problem if you know exactly what the file is. If you do not, then you may have to make a guess. You are right about the file extension. There is a well-known scripting language called PHP and its files end in those three letters. I have found some others, however. There are several sources for finding out what a file extension means. One of the best is Filext.com. A search shows that apart from the PHP scripting language, a few well-known graphics companies also use the extension, including Broderbund and Callisto Corp. Callisto's PhotoParade is fairly common, as it used to be distributed as part of Adobe's consumer photography product PhotoDeluxe. Microsoft also showed up with its Picture It imaging software, but little information on the file extension. (A search on the Microsoft website comes up with the PHP scripting language and points you to information on how to move on to the .Net platform.) Visit the website XnView ( www.xnview.com ) which has a free graphics program that can read a wide range of files or convert them to a standard. If none of this works, you may have to visit your relative and scan the picture yourself. She may have used a software package bundled with the scanner. Often these rather simple packages do not use standard data types. Questions to Tech Talk will not be answered personally. E-mail Danyll Will at firstname.lastname@example.org .