Last June, Google began ramping up its pursuit of Amazon by unveiling Google Compute Engine, a cloud-computing competitor to Amazon Web Services.

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Instances (virtual machine instances) are the heart of Google Compute Engine.

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One biggie was the announcement that any and all companies looking for computing horsepower can jump on board its formerly-limited Google Compute Engine, part of the Google Cloud Platform.

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Inside Google, Compute Engine was considered a "defensive" move against Amazon Web Services, according to a person familiar with the deliberations that led to the introduction of Google's service.

WSJ: Google Follows Amazon's Lead on New Shopping Site, Delivery, Other Services