API
API or Application Programming Interface is the interface of interaction between the website and third-party programs and servers.
The programmer can use the API to access the functionality of a third-party program. API ensures the operation of resources that use the potential and power of another website or program.
Using API eliminates the need to create complex programs or Apps. Instead, you can use ready-made parts of existing resources that have access to the information and data you need.
API usage examples
Each of you has probably registered on some online service or platform at least once via social media accounts. This is exactly what API usage is when services or Apps use social media databases. At the same time, the service can receive information about the user and use it for its own purposes.
Another example: Amazon recommends the user books based on the choice of books of his friends on Facebook. YouTube videos can automatically appear on your website or on your social media accounts. This is also possible due to the API, when one program uses the data and information of another. By the way, embedding YouTube videos on your website is possible thanks to the YouTube API service.