APIs are very versatile, but usually also specified on one particular data set. In order to achieve interesting, surprising and useful results, programmers often combine multiple sources of data. One frequently used interface is the Google Maps API. People love to map all sorts of things, whether it is important data such as global carbon emissions or less important things such as where the nearest Burger King is. Nevertheless, APIs can help a programmer with a lot of compelling problems. You will combine the Geolocations, Google Maps and Rijksmuseum APIs to create a new dataset.
Mashing up is the principle of taking the data of two or more APIs or datasets and combining these to create something new. Usually this is achieved by taking data and juxtapositioning it with other data in such a way that a surprising and interesting effect is achieved. For example, Wheel of Lunch takes a location and what you want to eat and randomly selects a place in your vicinity where you can get that food. It does so by consulting the Yahoo Local Search API. Sadly, it told us to get our sushi at the Albert Heijn, so it's not entirely flawless. This is just one of the many things that can be achieved with mashing up.
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Combining the geographical data from Geolocations and the data from the Rijksmuseum is the next step to understanding API's. Displaying the data in an actual map, however, is going to be quite challenging.
Check out the Plunker
Once you can use
Make the browser display the name of the artwork, the artist, the location(s) and their longitude and latitude
Not all artworks have locations and some have multiple, so decide yourself how to tackle this problem
You get bonus points if you display the locations on a map, but it is not manditory
Plunker: Plunker task