Micro Services
A microservice is a small, independent software component that performs one specific business function and communicates with other components over a network—usually through APIs.
In simple terms Instead of building one large application (a monolith), you build many small services that work together.
Key characteristics of microservices
- Single responsibility -Each microservice does one thing well (e.g., user authentication, payments, notifications).
- Independently deployable- You can update or redeploy one service without affecting others.
- Loosely coupled- Services communicate via APIs (HTTP/REST, gRPC, messaging queues).
- Technology independent - One service can use Java, another Python, another Node.js.
The communication happens via API calls generally.
Example : Imagine an online shopping application built using microservices. Instead of one large system handling everything, the application is divided into small independent services. The User Service manages customer accounts and login, the Order Service handles order creation and tracking, the Payment Service processes payments, the Inventory Service keeps track of available products, and the Shipping Service manages delivery. Each service runs separately and communicates with others through APIs. This means if the payment service needs an update or fails temporarily, the rest of the application—such as browsing products or viewing orders—can continue working without interruption.