Cloud Fundamentals 101

Course overview

You already use the cloud. Your phone backs up pictures to it. Your bank app runs on it. The streaming show you watched last night came out of it. This course pulls back the curtain so you can understand it, use it safely, protect your account and your money, and create two real things: a public website and a virtual computer.

DCT courses follow the same four moves every time: Understand → Use → Protect → Create. You will see those words at the top of every module.

What you will be able to do

By the end of this course you will be able to:

1. Explain cloud computing in plain language to a family member, a hiring manager, or a customer.
2. Tell the difference between IaaS, PaaS and SaaS and name an example of each.
3. Compare how AWS, Microsoft Azure and Google Cloud name the same core services.
4. Lock down a new cloud account with MFA, a budget alert, and a least-privilege habit.
5. Publish a static website from cloud storage.
6. Create, connect to, and delete a Linux virtual machine without leaving anything running that costs you money.
7. Read a cloud bill and explain what generated each charge.

Who this is for

What you need

• A computer (Windows, Mac, Linux or a Chromebook) and an internet connection.
• An email address you control and a phone for multi-factor authentication.
• A credit or debit card for cloud sign-up. Providers verify identity with a card. Following the cleanup steps keeps charges at or near zero, but you are responsible for what you create.
• About 6–8 hours, spread across as many days as you like.

How this course is built

How you are assessed

Earn 70% overall to receive the DCT Cloud 101 Certificate of Completion. This is a DCT credential, not a vendor certification.

Module 1 — Understand the cloud

Understand. Learning objectives: define cloud computing; describe the five essential characteristics; compare service models (IaaS, PaaS, SaaS) and deployment models (public, private, hybrid, multi-cloud); explain shared responsibility.

1.1 What the cloud actually is

The cloud is other people's computers that you rent over the internet, on demand, and pay for by usage. Those computers sit in giant buildings called datacenters, owned by companies such as Amazon (AWS), Microsoft (Azure) and Google (Google Cloud).

The U.S. National Institute of Standards and Technology (NIST SP 800-145) gives the official definition. Cloud computing has five essential characteristics:

Dope Translation: Owning servers is like buying a whole building to run a barbershop. You pay for the roof, the plumbing, the security, and the empty chairs on a slow Tuesday. The cloud is renting a chair by the hour. Busy Saturday? Rent ten chairs. Slow Tuesday? Rent one. You only pay for chairs with somebody in them.

1.2 CapEx vs. OpEx

• Capital expenditure (CapEx): big money up front for things you own — servers, buildings, generators. You pay before you know if the business will use it all.
• Operational expenditure (OpEx): pay as you go for what you use this month. Cloud is mostly OpEx.

Dope Translation: CapEx is buying the car. OpEx is taking a ride share. If you drive every day, owning may win. If you drive twice a month, renting rides is smarter. Businesses do the same math with servers.

1.3 The service models: IaaS, PaaS, SaaS

Dope Translationthe pizza model: - On-premises: you make pizza at home. You buy the oven, the flour, everything. - IaaS: you rent a kitchen with an oven. You bring ingredients and cook. - PaaS: you go to a make-your-own-pizza spot. They have the dough and oven; you pick the toppings. - SaaS: you order delivery. You just eat — and decide who gets a slice.

1.4 Deployment models

• Public cloud: shared provider infrastructure, available to anyone with an account. Most of this course.
• Private cloud: cloud-style infrastructure used by one organization only, on-premises or hosted.
• Hybrid cloud: public and private connected and working together. Common in government and banks.
• Multi-cloud: using more than one public provider (for example Azure for identity and email, AWS for a specific app).

Real Talk: A county agency keeps resident records in its own datacenter because of a records law, but runs its public website and email in the public cloud. That is hybrid. When the same agency also uses Google Workspace for a youth program, it is multi-cloud too.

1.5 Shared responsibility — the most important idea in this course

The provider secures the cloud itself (buildings, hardware, the network between datacenters). You secure what you put in the cloud (your data, your accounts, who has access, the settings you choose). As you move from IaaS to PaaS to SaaS, the provider takes on more — but you always own your data, your identities and your access decisions.

Dope Translation: You rent a storage unit. The company owns the fence, the gate, the cameras and the building. But if you leave your unit unlocked, or hand your code to everybody in the group chat, that's on you. Most cloud breaches aren't hackers breaking the fence. They're unlocked units.

1.6 The big three, side by side

Takeaway: Learn the concept once. The names change; the ideas do not.

1.7 Regions and availability zones

• A region is a geographic area with one or more datacenters (for example East US or us-east-1, both in Virginia).
• An availability zone is a physically separate datacenter (or group) inside a region with its own power, cooling and networking.
• Put copies of important things in more than one zone so one building's outage does not take you down.

Dope Translation: Don't keep all your money in one shoebox. A zone is a second shoebox in a different room. A second region is a shoebox at your aunt's house across town.

Module 1 knowledge check