SOA is an architectural style rather than a product.
SOA is an architecture to help the business and IT teams work together and think about IT infrastructure in the way business needs.

By organizing enterprise IT around services instead of around applications, SOA provides key benefits:
* Improves productivity, agility and speed for both Business and IT
* Allows IT to deliver services faster and align closer with business
* Allows the business to respond quicker and deliver optimal user experience
* Masks the underlying technical complexity of the IT environment
This results in more rapid development and more reliable delivery of new and enhanced business services.

Business Benefits of Service-Oriented Architecture

Efficiency: Transform business processes from siloed, replicated processes into highly leveraged, shared services that cost less to maintain.
Responsiveness: Rapid adaptation and delivery of key business services to meet market demands for increased service levels to customers, employees, and partners.
Adaptability: More effectively rollout changes throughout the business with minimal complexity and effort, saving time and money.

IT Benefits of Service-Oriented Architecture:

Reduced Complexity: Standards-based compatibility versus point-to-point integration reduces complexity
Increased Reuse: More efficient application/project development and delivery through the reuse of shared services, previously developed and deployed
Legacy Integration: Legacy applications, leveraged as re-usable services, lowers the cost of maintenance and integration

A service-oriented architecture is a collection of services that communicate with each other. The services are self-contained and do not depend on the context or state of the other service. They work within a distributed systems architecture.

SOA adds flexibility to business processes and the applications that drive them by breaking them down into smaller functional elements called services, then assembling them into applications to achieve standardization and interoperability

Service-Oriented Architecture is an IT strategy that organizes the discrete functions contained in enterprise applications into interoperable, standards-based services that can be combined and reused quickly to meet business needs.