A microservices architecture differs from a monolithic architecture in that it structures an application as a collection of small, independently deployable services. Each service focuses on a specific business capability and communicates with others through well-defined APIs. This modularity allows for greater scalability, as teams can develop, deploy, and scale services independently. In contrast, a monolithic architecture integrates all functionalities within a single codebase, which can hinder flexibility and make updates more challenging. Microservices also facilitate easier adoption of new technologies and languages, promoting continuous integration and delivery.