1.1 Cloud Computing Fundamentals

Azure fundamentals introduces cloud computing through Microsoft Azure, focusing on core cloud concepts, deployment models, and how responsibility is shared between a cloud provider and the customer.

Microsoft Azure and the scope of Azure Fundamentals

Microsoft Azure is a cloud computing platform with an expanding set of services for building solutions that meet technical goals. Azure supports workloads ranging from simple internet-facing web services to fully virtualized computers for custom software, as well as managed services such as remote storage, database hosting, and centralized account management. Azure also includes capabilities for artificial intelligence (AI) and Internet of Things (IoT).

Azure Fundamentals is a series of three learning paths that familiarize you with Azure services and features, plus one learning path that lets you explore Azure by building solutions to realistic IT challenges. It is designed as a curated guide across areas such as compute, networking, storage, cloud security best practices, and governance/management options. Technical IT experience isn’t required, but general IT knowledge helps.

Why Azure Fundamentals and how it maps to AZ-900

Azure Fundamentals can help both beginners and those with prior cloud experience get started with Azure. It can also help you prepare for Exam AZ-900: Microsoft Azure Fundamentals, which is organized into three knowledge domains with relative weights. Higher percentages indicate more questions in that exam area.

What cloud computing is (and why it changes planning)

Cloud computing is the delivery of computing services over the internet. These services include traditional IT infrastructure—virtual machines, storage, databases, and networking—and also extend to newer offerings such as IoT, machine learning (ML), and AI. Because services are delivered over the internet, cloud computing is not constrained by physical infrastructure in the same way as a traditional datacenter, enabling rapid expansion of IT capacity without waiting to build new facilities.

Practical example: a retail team anticipating seasonal traffic can deploy extra compute capacity in the cloud for the launch period and scale down afterward. At a fundamentals level, this shifts planning from long procurement cycles to on-demand provisioning, helping teams test faster, recover faster, and adapt capacity as requirements change. Cloud platforms can also provide global reach, allowing services to be placed closer to users and designed for regional resilience without building multiple physical datacenters.

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Shared responsibility model: how duties shift in the cloud

In a traditional on-premises datacenter, your organization is responsible for maintaining the physical space, security, and the servers themselves, and the IT department maintains the infrastructure and software needed to keep the datacenter running (including patching and versioning). In cloud computing, responsibilities are shared between the cloud provider and the consumer. The provider takes responsibility for physical security, power, cooling, and network connectivity, while the consumer remains responsible for the data and information stored in the cloud and for access security (granting access only to those who need it).

Some responsibilities depend on the service model and how you deploy a solution. For example, if you use a cloud SQL database service, the provider maintains the database platform, but you are still responsible for the data you ingest. If you deploy a virtual machine and install an SQL database on it, you are responsible for database patches and updates as well as the data. The shared responsibility model is closely tied to cloud service types: infrastructure as a service (IaaS) places more responsibility on the consumer; software as a service (SaaS) places more on the provider; and platform as a service (PaaS) sits between them.

• Consumer is always responsible for: information and data stored in the cloud; devices allowed to connect (phones, computers, etc.); and accounts/identities of people, services, and devices in the environment.

• Provider is always responsible for: the physical datacenter, physical network, and physical hosts.

• Depends on service type: operating systems, network controls, applications, identity and access, and infrastructure.

Example of shared duties: in PaaS and SaaS, identity and access is shared—you manage users, roles, and policies, while the provider runs the authentication platform (such as Microsoft Entra ID). Infrastructure shifts entirely to the provider once you move from on-premises to IaaS.

Cloud deployment models: private, public, hybrid, and multicloud

Cloud models describe the deployment type of cloud resources. The three main models are private, public, and hybrid. A fourth increasingly common scenario is multicloud (using multiple public cloud providers).

Private cloud

A private cloud is a cloud environment used by a single entity. It evolved from the traditional datacenter model by delivering IT services over the internet while keeping resources dedicated to one organization. It provides greater control for the IT team, but typically comes with greater cost and fewer public-cloud benefits. A private cloud may be hosted in an on-site datacenter or in a dedicated offsite datacenter, potentially run by a third party.

Public cloud

A public cloud is built, controlled, and maintained by a third-party cloud provider. Anyone who wants to purchase cloud services can access and use resources; this general public availability is a key difference from private cloud.

Hybrid cloud

A hybrid cloud uses both public and private clouds in an interconnected environment. One use case is “surging,” where a private cloud temporarily deploys public cloud resources to meet increased demand. Hybrid cloud can also add security flexibility by letting organizations choose which services remain in public cloud and which run on private infrastructure.

Multicloud and Azure management/migration options

In a multicloud scenario, you use two or more public cloud providers—often to use different features across providers or while migrating from one provider to another. This requires managing resources and security across multiple providers. Azure Arc is a set of technologies that helps manage environments across Azure-only public cloud, private cloud, hybrid configurations, and multicloud. If you have VMware-based private cloud workloads and want to move to public or hybrid cloud, Azure VMware Solution lets you run VMware workloads in Azure with integration and scalability.

Consumption-based model and cloud pricing

Cloud computing uses a consumption-based model: you pay for the IT resources you use and nothing more. Instead of buying and maintaining datacenter infrastructure, you rent compute and storage and release resources when you’re done. This aligns with operational expenditure (OpEx)—ongoing spending on services over time—rather than capital expenditure (CapEx), which is up-front spending on physical infrastructure such as servers, network hardware, and datacenter space.

• No upfront costs for hardware or datacenter infrastructure.

• No need to purchase and manage capacity that may go underutilized.

• Ability to add resources when demand increases.

• Ability to release resources when demand decreases.

Capacity planning differs sharply between traditional datacenters and cloud. In a traditional datacenter, you estimate future needs: overestimating wastes money on idle infrastructure, while underestimating degrades performance and requires ordering and provisioning more hardware (plus power and cooling). In the cloud, you adjust resources to match actual demand—for example, add virtual machines during peaks and remove them when demand drops—paying for used capacity rather than idle capacity.

Cloud providers typically use pay-as-you-go pricing. Paying only for consumed services helps plan and manage operating costs, run infrastructure more efficiently, and scale as workload needs change. The provider maintains underlying infrastructure (power, cooling, hardware, networking), allowing teams to focus on business problems and delivering new capabilities.