This book is focused on public cloud providers, which, in the fullness of time, will most likely be the dominant way companies consume IT resources. The cloud, as it is today, began in 2006 when Amazon Web Services (AWS) launched its first public services (Amazon Simple Queueing Service and Amazon Simple Storage Service). From there, they raced to add features at a very fast pace of innovation, with virtual server instances, virtual networking, block storage, and other foundational infrastructure services. In 2010, Microsoft released Azure, similar to AWS, with features designed to mimic what AWS had started and compete for customers in this space. Also during this time, Google began releasing more platform services, which ultimately became Google Cloud Platform, where it stands today.

While there are other clouds out there, with different niche focus areas and approaches to addressing customer requirements, these three comprise the dominant global market share for cloud services. Making the decision on a cloud vendor can appear complex when originally researching the vendors, mainly because less dominant players in the space try to position themselves as better situated than they are by showing cloud revenues or market share on services that are really not cloud at all. Since there is no one definition of a cloud and how to report revenues for it, and each company can say whatever they want about their services, it's important to understand the richness and scale that a cloud vendor has before making decisions. Each of the three major cloud vendors have very compelling foundational services (often referred to as Infrastructure as a Service) and have moved into higher-value managed cloud offerings (sometimes referred to as Platform as a Service), which offer everything from databases, to application services and Devops tools, to artificial intelligence and machine learning services.

There are many criteria that customers consider when choosing a cloud vendor, some of which have to do with the technology they have used in the past and are comfortable with. Some additional areas to consider are as follows:

• Scale: The cloud vendor business is one of scale and ability to deliver anywhere at any time. Even if a customer doesn't currently need cloud resources on a global scale, or to do a massive scale out in a single geography, using a cloud vendor that can do this is critical to ensure they have the experience, funding, and desire to continue to grow and innovate.
• Security/compliance: The priority of all cloud vendors should be security. If a cloud vendor doesn't focus on this and already has the majority of compliance certifications, it is best to stay clear and choose a vendor that makes this a priority.
• Feature richness: The pace of innovation is ever increasing and cloud vendors are moving into areas that were not even considered a few years ago. Whether it be machine learning, blockchain, serverless, or some other new technology, the cloud vendors that are constantly innovating are the ones to focus on.
• Price: While never the sole a reason to choose a vendor, price should always be considered. Contrary to popular belief, the cloud vendor market is not a race to the bottom in terms of pricing. Scale and innovation allow vendors to lower prices by passing along savings to customers (another reason why scale matters). The three major cloud vendors are all cost competitive at this point, but it's important to continuously monitor the price of services.

Gartner has for many years done deep analysis on the cloud vendor market. The most recent version of the Gartner magic quadrant for cloud infrastructure services can be found here: https://www.gartner.com/doc/3875999/magic-quadrant-cloud-infrastructure-service.