Mashups
In distributed GIS, the term mashup refers to a generic web service which combines content and functionality from disparate sources; mashups reflect a separation of information and presentation. Mashups are increasingly being used in commercial and government applications as well as in the public domain.
When used in GIS, it reflects the concept of connecting your application with a mapping service (e.g., combining Google maps with Chicago crime statistics to create the ).
Mashups are fast, provide value for money and remove responsibility for the data from the creator.
Second generation systems provide mashups mainly based on URL parameters, while Third generation systems (e.g. Google Maps) allow customisation via script (e.g. JavaScript).
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