Why pay for software I already have?
Shareware is a method of software distribution and marketing, and not a type of program. In fact, try-before-you-buy software has been discovered by traditional "shelfware" companies, and now, nearly every large software company provides some type of free trial version of their software. Some of those trial versions are shareware, and some aren't. Shareware, traditionally, is software that is published by authors who want you to help with their word-of-mouth advertising. It's more than a free trial; it's a free trial that you can share with your friends. When you find a product that does what you need, you'll buy the full version, usually directly from the author, and nearly always find that if you need product support, you'll get a fast answer from a programmer who worked on the product, and not some help-desk worker reading from a pre-programmed script.