The computer saw the pace of change announcements and Buzz, which makes it difficult to differentiate a true revolution of a simple evolution. At one time it was thought that a software package integrated with a monolithic view, will meet the needs of the business, and now the leaders of the ERP SAP to Oracle through Miscrosoft we "cram" lectures on the virtues of SaaS, or even launch offers "real" in this model (SAP, ...).
SaaS stands for Software as a Service. This is a technology of providing services or software through the Web rather than through a desktop application or client-server. The SaaS concept, emerged in the early 2000s, is promoted to take the place of the Application Service Provider (ASP).
SaaS will offer us a new generation of software, modular and flexible, organized into reusable business services, configurable, accessible via the Web (or simply via the corporate network), while respecting the contract a SLA and QoS.