17. The Cloud and Distributed Computing
A distributed system is one in which the failure of a computer you didn’t even know existed can render your own computer unusable.
Cloud computing is about the on-demand availability of resources. This term is used to refer to a wide range of computing capabilities. For example, you might say, “All my photos are backed up to the cloud.” But what does that mean? It means:
• My photos are stored on someone else’s computers. They worry about the capital investment and maintenance and upkeep and backups.
• My photos are accessible by me over the Internet.
• I pay only for the space that I use, or that I requisition.
• The storage service is elastic, meaning that it can grow or shrink as my needs ...