Difference b/w SOA and SOAP

SOA ( service-oriented architecture)

There are a lot of definitions of Service Oriented Architecture, some of which are: 

A service Oriented Architecture is a set of components which can be invoked and 

whose interface descriptions can be published and discovered. 

SOA is an architectural style whose goal is to achieve loose coupling among 

interacting software agents. A service is a unit of work done by a service provider to 

achieve desired end results for a service consumer. Both provider and consumer are 

roles played by software agents on behalf of their owners.

Service-oriented architecture (SOA) is an architectural software concept that defines 

the use of services to support business  requirements. In an SOA, resources are 

made available to other participants in the network as independent services that are 

accessed in a standardized way. Most definitions of SOA identify the use of web 

services (using SOAP, WSDL and UDDI) in its implementation; however it is possible 

to implement SOA using any service-based technology. 

SOAP (Simple Object Access Protocol)
One of the most significant characteristic  of Web Services is their loose coupling.

They are not only independent from the infrastructure they are running on. It doesn’t

make any difference (in contrast to Component-based Architecture) if one service

using another doesn’t run on the same computer, or doesn’t use the same

language/operating system. Web Services released with .NET can easily be coupled

with Web Services written in Java, as if both were Java or .NET builds. 

In addition, they can be exposed to the internet so that everyone can use

components he is not the owner of, without taking them away from their owner, or

having to copy them. Web Services are designed to be published as far as possible

like web sites. They should be like web site for machines and computers.