API stands for application programming interface. An API is a protocol that allows a user to query a resource and retrieve and download data in a machine-readable format. Researchers sometimes use APIs to download collections of texts, such as scholarly journal articles, so they can perform automated text mining on the corpus they've downloaded.
Here is a simple tutorial that explains what an API is.
Below are some APIs that are available to researchers. Some are open to the public, while others are available according to the terms of Temple University Libraries' subscriptions. Many require you to create an API key, which is a quick and free process.
You can create a simple query in the address bar in a web browser. However, a more complex query generally requires using a programming language. Commonly used languages for querying APIs are Python and R. (R is the language used in the R software.) The examples given in the documentation for the APIs listed below typically do not include sample programming code; they only explain how the data is structured in order to help users write a query.
We would like to acknowledge API guides created by the Libraries at MIT, Berkeley, Purdue and Drexel that informed our work on this guide.