Here is a fun fact; Facebook is or was based on cloud computing. Cloud computing consists of three types of computing services: (1) software as a service; (2) platform as a service; and (3) infrastructure as a service. Facebook used Amazon.com's EC2 platform to build its social network website. A computer platform is the computing environment that consists of is some sort of hardware architecture and software framework (including application frameworks) that allow software to run.
Red Hat CEO Jim Whitehurst said that cloud computing is heavily dependent on open source software and that 90 percent of today's clouds leverage open source software. For consumers of software as a service, the existence of open source software in a software program is not an issue because the customer is not receiving a license to create a derivative work of the computer code. However, for the customers (like Facebook) that use platform as a service, the existence of open source software can be a real issue. For a software program to work within a particular computing environment, some linking of the program with the environment is necessary. Depending upon how the software program links with the environment could subject the software program to whatever open source software licenses govern the environment.
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