Application Programming Interfaces
API is an acronym for "Application Programming Interface". It’s the mediator (represented by a piece of software) between applications/websites and you as a user. Therefore, it is vital for communication between different instances to exchange information.
You encounter APIs in everyday life without you realizing it. An example is Google Search: Every time you enter something into the search bar, Google's backend service looks up your keywords in its database and lists your request's results on the website. Actually, the website displays the API's result. An indicator for this is the URL of the respective search.
When thinking of a search for "SAP", the URL states: www.google.com/search?q=sap.
Now let us slice this one down:
Here www.google.com is the server address, /search indicates the feature you intend to use or better the API you want to call, which in this case is the Google Search API, and q (for query) tells it that now a value for query is handed over, which is the search term.
The same applies to SAP's help page (https://help.sap.com). When entering API into the search bar, the following URL comes up: https://help.sap.com/docs/search?q=api.
However, an API call doesn't necessarily have to be initiated by a computer. Voice assistance systems are also an example of the integration and use of APIs. Asking your voice assistant to search for something actually provides the assistant with your query. This query is then stored as text and added as the query to the API call. Afterward, the assistant gives out the API’s result via audio voice.
So, no matter what you do with any of your connected devices, you are using several APIs per hour without noticing. This is why APIs are such an important topic, because they are omnipresent and enable users and developers to focus on "what" needs to be done and not "how". Or have you ever thought about how your WhatsApp message gets sent to a recipient?
Therefore, as the name suggests, an API is just one of many types of interfaces used to trigger specific functions, for example, playing music. You might already be familiar with other types of interfaces, such as GUI (Graphical User Interface), which we use to navigate across applications/websites with the help of a mouse/touchscreen.