Cloud concepts are the base layer of AZ-900. If these ideas are unclear, Azure service questions become harder than they need to be. The goal is not to memorize every product name first. The goal is to understand why cloud computing changes how organizations buy, scale, secure, and operate technology.
Concepts to know well
Start with shared responsibility. In cloud computing, security and operations are split between the cloud provider and the customer, and that split changes depending on whether a service is IaaS, PaaS, or SaaS. This is one of the most useful ideas for answering scenario questions.
Next, separate cloud deployment models. Public cloud uses provider-owned infrastructure. Private cloud is dedicated to one organization. Hybrid cloud combines environments. Multi-cloud uses more than one cloud provider. These definitions sound simple, but exam-style questions often hide them inside business requirements.
Also review consumption-based pricing, elasticity, scalability, high availability, reliability, disaster recovery, and governance. These terms explain why an organization might choose cloud services instead of buying and maintaining all infrastructure itself.
How this domain links to the rest of AZ-900
Cloud concepts prepare you for the heavier service and governance domains. Once the vocabulary is solid, move to the AZ-900 exam objectives to see where the domain fits in the full outline. Then use the AZ-900 Practice Test to check whether you can apply the terms in short questions.
If your simulator misses mostly come from confusing IaaS, PaaS, and SaaS, stay on this page a little longer. If your misses mention Azure Policy, cost controls, or monitoring, move your review toward management and governance instead.
Verified against the official vendor reference: learn.microsoft.com.