Short for Software as a Service, SaaS is a software delivery method that provides access to software and its functions remotely as a Web-based service. SaaS allows organizations to access business functionality at a cost typically less than paying for licensed applications since SaaS pricing is based on a monthly fee. Also, because the software is hosted remotely, users don't need to invest in additional hardware . SaaS removes the need for organizations to handle the installation, set-up and often daily upkeep and maintenance. Software as a Service may also be referred to as simply hosted applications.
 
演示ex:
Document Management as a Service 
SpringCM falls in the growing software-as-a-service (SaaS) category, so there's never anything to install on your end, either upfront or for upgrades. The company handles all maintenance and upgrading. You even add new members online.
SmallBusinessComputing.com 
Provides technology solutions for small business owners, hardware/software reviews, webmaster resources and news.
ZDNet - Software as Service Blog
Applications on demand. Written by Phil Wainewright, strategist on emerging software industry trends.
 
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