What is TWAIN?

Question: What is TWAIN?


Some say TWAIN stands for "technology (or toolkit) without an interesting name," but that's a myth. What matters is what TWAIN does. Released in 1992, Twain is the interface standard for Windows and Macintosh that allows imaging hardware devices (such as scanners and digital cameras) to communicate with image processing software. Prior to TWAIN, image acquisition devices all came with their own proprietary software.

If you wanted to work with a scanned image in a different application, you had to save the image to disk first, then open the application of your choice and re-open the image there.

Nearly all image processing software today is TWAIN compliant. If your software supports TWAIN, you will find an "Acquire" command in the menus or toolbars (though sometimes the command is hidden under an Import menu). This command provides access to any TWAIN hardware devices installed on the system. Although the software appearance and capabilities for each device can vary, the TWAIN Acquire command calls up the hardware interfacing software, and places the acquired image into the image processing software, without the need for the image to first be saved to disk.

So what does TWAIN really stand for? According to The Free On-line Dictionary of Computing and substantiated by the TWAIN Working Group's official Web site, it's not an acronym at all:

The word TWAIN is from Kipling's "The Ballad of East and West" - "...and never the twain shall meet...", reflecting the difficulty, at the time, of connecting scanners and personal computers. It was up-cased to TWAIN to make it more distinctive. This led people to believe it was an acronym, and then to a contest to come up with an expansion. None were selected, but the entry "Technology Without An Interesting Name" continues to haunt the standard.
-The Free On-line Dictionary of Computing, Editor Denis Howe

A common use of TWAIN is to allow the scanning of images directly into Photoshop. This has became increasingly more difficult starting with the release of Photoshop CS5 and continues to this day. The main reason being Adobe dropped support for 64-bit TWAIN scanners in either 64-bit or 32-bit Photoshop, and also suggests you use TWAIN "at your own risk". CS6 only runs in 64-bit mode: if your scanner driver can’t handle 64-bit mode, you may not be able to use TWAIN.  In fact , TWAIN just may be a technology on its last legs. Thankfully, Adobe has some suggestions around replacements.

Updated by Tom Green

Graphics Glossary