Each software is released under a type of license which can be found on program pages as well as search or category pages. Here are the most common license types:
Free programs can be downloaded used for free and without time limit. Free products can be used free of charge for both personal and professional use (commercial use).
Open source software is software whose source code can be inspected, modified or improved by anyone. Programs released under this license may be used free of charge for personal and commercial purposes. There are many different open source licenses, but they must all conform to the definition of open source – in short: the the software can be freely used, modified and shared.
free to play
This license is commonly used for video games and it allows users to download and play the game for free. Basically, a product is offered for free (Freemium) and the user can decide whether he wants to pay money (Premium) for additional features, services, virtual or physical goods that expand the functionality of the game. In some cases, advertisements may be served to users.
The demo programs have a limited functionality for free, but charge for an advanced set of features or for removing ads from program interfaces. In some cases, all features are disabled until the license is purchased. Demos are generally not time-limited (like trialware), but functionality is limited.
The trial software allows the user to evaluate the software for a limited time. After this trial period (usually 15 to 90 days), the user can decide whether or not to purchase the software. Although most trial software products are only time-limited, some also have feature limitations.
Generally, commercial software or games are produced for sale or to serve a commercial purposes.