What is a composite API?

• A. API that provides real-time data
• B. API that builds multiple data calls into a single endpoint
• C. API that exposes only internal systems
• D. API that is publicly available to all users

Answer: (B)

A composite API is designed to aggregate multiple API calls into a single endpoint, allowing clients to access multiple resources in a single request. This is particularly beneficial when a client needs to fetch data from various sources or services simultaneously, as it reduces the number of requests made over the network, minimizes latency, and optimizes performance. By consolidating data retrieval into one call, a composite API can streamline client interactions and simplify the architecture of applications that need to interact with multiple services.

In contrast, the other options focus on different characteristics of APIs and do not accurately describe the function of a composite API. An API providing real-time data centers on the timeliness and immediacy of the information it delivers, while one that exposes only internal systems limits its accessibility to internal stakeholders. Lastly, an API that is publicly available refers to its accessibility by all users but does not imply any specific function like the aggregation of requests that distinguishes composite APIs.