Final answer:
The API Gateway acts as a single entry point for client requests to access different APIs. It manages and controls API traffic, security, and policies. It also provides API versioning, authentication and authorization, and enables API composition.
Step-by-step explanation:
The API Gateway, also known as APIM (API Management), is a component of a system that acts as a single entry point for all client requests to access different APIs. It provides a centralized way to manage and control API traffic, security, and policies. The API Gateway acts as a reverse proxy, forwarding client requests to the appropriate backend services and returning the responses back to the client.
One of the main functions of an API Gateway is to provide API versioning. This allows different versions of an API to coexist without breaking existing clients. The API Gateway can also handle authentication and authorization, enforcing security measures before allowing requests to be forwarded to the backend services.
Another important role of an API Gateway is to enable API composition. It can aggregate multiple backend services or microservices into a single API, simplifying the client's interaction and reducing the number of requests they need to make. This can improve the overall performance and efficiency of the system.