All licenses or End User License Agreements (the foundry’s terms you agree to before downloading their fonts) are prominently displayed on each foundry page. For example, here’s Frode Helland and Sindre Bremnes’ foundry, Monokrom. Find the link just below the foundry description text. Links to the corresponding license are also at the bottom of each family page, and at checkout. At the top of each family page, find a concise graphic on the line just below the Buy button showing which licenses and formats are included. For example, FF Quixo is available for desktop, web, and mobile.
Desktop fonts are licensed based on the number of users. Within desktop, there are two main font formats our foundries deal in: OT (OpenType), and TT (TrueType). Though the technical differences between these two formats once determined compatibility with different systems, they’re now essentially interchangeable. TrueType fonts remain the standard for interoperability between PC and Mac platforms, while OpenType fonts are the most readily accepted by print houses and service bureaus in the graphic arts industry. The creation of the OpenType format in the late 1990s brought with it greater character capacity and rich substitution features, which gave a single font the ability to include both upper & lowercase and small caps, for example, and allow the typographer to easily highlight a passage and switch between the two.
The webfonts that FontShop carries are self-hosted, the kind you host on your own webserver*. These are usually licensed for a single website, and based on the estimated number of pageviews over a specified period of time. The industry standard formats for webfonts are WOFF (Web Open Font Format), and EOT (Embedded OpenType). These are marked simply 'Web' on the FontShop site.
Embeddable fonts for eBooks, apps, games, and editable PDFs, including FontFont's App+ fonts are licensed over a given period of time, and then renewed as needed. TrueType is the standard format for embedded fonts.