A collection of services. These services communicate with each other. The communication can involve either simple data passing or it could involve two or more services coordinating some activity.
						                            Source(s):
						                            
								                            
                                                                    NIST SP 800-95
										                            
                                                                            Open Grid Services Architecture Glossary of Terms (25 January 2005)									                            
						                            
						                            
						                        
					                            
						                              A set of principles and methodologies for designing and developing software in the form of interoperable services. These services are well-defined business functions that are built as software components (i.e., discrete pieces of code and/or data structures) that can be reused for different purposes.
						                            Source(s):
						                            
								                            
                                                                    NIST SP 800-53 Rev. 4
										                             under Service-Oriented Architecture