Stands for “Application Programing Interface”
A way to exchange data between servers / services (i.e. software to software communication)
Set of programming instructions and standards for accessing a service, tool or application
For example, Amazon.com released its API so that Web site developers could more easily access Amazon’s product information
In a nutshell, if you want to leverage information from another website or application your first choice should be to use an API (if they offer one)
Does the website I need data from even have an API?
Do I need to authenticate with the remote data source before retrieving the information I need, either as an API consumer or as a user of that service?
What are the URLs I use to access the data I need?
If the website you need data from does not have an API, you could resort to data scraping through the use of “spiders” which crawl websites and extracts information
Many online services consider data scraping to be a violation of their Terms of Service
The “modern standard” for API responses is JSON, or JavaScript Object Notation
Some APIs are implemented using XML, this includes the API for WordPress, which is implemented using the XML-RPC standard
When making an API call, you are essentially making an Request to a server and then receiving a Response
Most of the time this response will contain data that you will make use of within your application