<P> There are many types of shareware, and while they may not require an initial up - front payment, all are intended to generate revenue in one way or another . Some limit use to personal non-commercial purposes only, with purchase of a license required for use in a business enterprise . The software itself may be limited in functionality or be time - limited, or it may remind the user that payment would be appreciated . </P> <P> Adware, short for "advertising - supported software", is any software package which automatically renders advertisements in order to generate revenue for its author . The advertisements may be in the user interface of the software or on a screen presented to the user during the installation process . The functions may be designed to analyze which Internet sites the user visits and to present advertising pertinent to the types of goods or services featured there . The term is sometimes used to refer to software that displays unwanted advertisements . </P> <P> On Microsoft Windows, shareware is often packaged with adware . During the install of the intended software, the user is presented with a requirement to agree to the terms of click through licensing or similar licensing which governs the installation of the software . </P> <P> Demoware is a demonstration version of software . There are generally two types demoware: that which is crippled, and that which has a trial period . </P>

Who is considered to be the inventor of shareware