Service-oriented architecture is a software development method that uses software components called services to create business applications.
Each of these services provides an enterprise capability and, in addition, they can also communicate with the rest of the services through different platforms and languages. Developers use SOA to reuse services on different systems or combine several independent services to perform complex tasks.
For example, a variety of business processes in an organization require user authentication functionality. Instead of rewriting the authentication code for all business processes, you can create a single authentication service and reuse it for all applications.
Similarly, almost every system in a healthcare organization, such as patient and administration systems and electronic health record (EHR) systems, needs to register patients. Such systems may call a single common service to perform the task of patient registration.

BENEFITS
Reduced time to market
Developers reuse services across different business processes to save time and money. They can build applications in less time with SOA instead of writing code and performing integrations from scratch.
efficient maintenance
Small services are easier to create, update, and fix than large blocks of code in monolithic applications. Modifying a service in SOA does not affect the overall functionality of the business process.
Excellent adaptability
SOA adapts better to technological advances. You can modernize your applications efficiently and cost-effectively. For example, healthcare organizations can use the functionality of older electronic health record systems in newer cloud-based applications.