Often, in cloud computing, we talk about availability. After all, we use the cloud to build high availability applications, right? When pressed to explain exactly what is meant by availability, people seem to be stuck at an answer. “A system that is not ‘down’, er, I mean ‘Up” is not good enough, but very common. So I had a crack at my own definition, starting of by describing availability outcomes and influencers. Have a look at Defining application availability and let me know what you think.