Lou wrote: >> You can be sure pdf software will be dinosauric in the next century. Descriptions from our era might be very difficult to locate then.... Speaking as a computer guy, file formats are not nearly as big a problem as hardware formats. Companies eventually stop making the hardware readers for things like floppy drives, and even cable connectors go out of use over time. Obscure file formats also go out of use. But if a file format was popular in the past and is well documented, companies tend to keep it in their apps as a checkoff item. And if not, the Internet has made it easy to find file converters. For example, Roger's Word Perfect 5.1 file is easy to open on a PC today. The hard part is getting it off that old floppy disk. PDF is about the closest thing we have to a universal document format today. I'm sure it'll be replaced by something better in the future, but because there are so many documents stored in it, I'm confident that we're going to be able to continue reading it for as long as we have digital data. Mike San Jose, CA