Core Cloud Services

You already know the 3 service models a provider can package its offerings into. This topic opens the boxes those models are built from: the actual services almost every cloud application, on any provider, is assembled out of. You start with how providers organize their infrastructure geographically, then move through compute, storage, databases, and networking, the same 5 building blocks whether you are reading an AWS architecture diagram, an Azure one, or a Google Cloud one.

What This Topic Covers

• Regions and Availability Zones: how providers isolate infrastructure geographically, and why spreading an application across zones is what actually protects it from a single data center's failure
• Compute services: virtual machine families and sizing, vertical versus horizontal scaling, managed compute platforms, and where containers and serverless functions sit on the same control-versus-convenience spectrum
• Storage services: object, block, and file storage, told apart by how each one organizes data and which access pattern each one fits
• Databases in the cloud: what a managed database service takes over, and how to choose between a relational database and a NoSQL database for a given workload
• Cloud networking basics: virtual private clouds, public and private subnets, security groups versus network ACLs, and how a load balancer spreads traffic across healthy instances

Why It Matters

These 5 services are not abstract vocabulary, they are the actual pieces a job posting means when it asks for "cloud infrastructure experience." A team that can name a service model but cannot say why a database belongs in a private subnet, or why a photo library belongs in object storage instead of a block volume, cannot actually design a working system.

Exam questions in this space test exactly this kind of applied judgment: a scenario describes a workload, and the correct answer depends on matching its access pattern, its availability requirement, or its exposure to the internet to the right building block. The Modern Cloud Architectures topic that follows assumes you can already place compute, storage, databases, and networking correctly, since every pattern it covers, serverless computing, containers, infrastructure as code, is built by combining these same 5 pieces in a new shape.