From the beginning of Microsoft's mobile efforts in the PDA era, its touchscreen phone software has had a Start button and windows that could be minimized like the classic Windows desktop.

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In the brave era of cloud computing, software is sold on a subscription basis and delivered on-demand over the Web.

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As demand for standalone anti-virus software wanes in the post-PC era, the need for securing and managing devices rises greatly.

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In many ways, much of the online learning courses look like software from the 1990s, not what one might expect in the era of Netflix in the 2000s.

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And software's influence and value have grown exponentially in the era of the PC and the Internet.

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That could hurt Microsoft as many companies refashion themselves for the era of "cloud" computing, a Google-backed approach in which software is easily accessed online and sold as a subscription product, rather than installed on companies' computers.

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Meanwhile, the construction of a new data center in North Carolina may herald an era of tighter integration between software and services at Apple.

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In an era of consumerized IT and packaged software solutions, increasingly delivered as a service from the cloud, it is tempting to think that vendors can be a good source for your IT strategy, relegating the CTO role to a sideshow.

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