An API call is a request made by a software application to a server, asking for specific data or services. The term "API" stands for Application Programming Interface, which is a set of rules that allows different software programs to communicate with each other. When an application makes an API call, it sends a request to the server, which processes it and returns the requested information. API calls are essential for enabling various functionalities in applications, such as retrieving data from a database or interacting with external services like social media platforms. They help developers integrate different systems and enhance user experiences by providing seamless access to information and services.