What Is Cloud Computing? A Simple Guide for Students

When people say an app "runs in the cloud", they mean it runs on computers in someone else's data centre, rented over the internet, instead of on a server in the company's own office. That is all the cloud is: other people's computers, offered as a service you pay for by the hour or by use.

It matters because almost every company you will apply to, from start-ups to banks, now builds on the cloud. Even a basic understanding puts you ahead of students who have only run code on their own laptop.

Why companies moved to the cloud

• No waiting for hardware: a new server is ready in minutes, not weeks.
• Pay for what you use: a small app costs little, and capacity grows when traffic grows.
• Managed services: the provider runs databases, backups and security patches, so the team can focus on the product.
• Global reach: the same app can be served from data centres in Mumbai, Singapore or Frankfurt.

IaaS, PaaS and SaaS in one minute

Think of food. Infrastructure as a Service (IaaS) is renting a kitchen: you get virtual machines, storage and networks, and you cook everything yourself. Examples are AWS EC2 and Google Compute Engine.

Platform as a Service (PaaS) is a kitchen with a cook: you bring the recipe (your code) and the platform runs it. Examples are Google Cloud Run, Azure App Service and Firebase.

Software as a Service (SaaS) is ordering the meal: you simply use finished software, like Gmail, Zoom or Salesforce.

The big three providers

Amazon Web Services (AWS), Microsoft Azure and Google Cloud Platform (GCP) are the largest. Their ideas are the same: compute, storage, databases, networking and identity. Learn one properly and the others become much easier, because mostly only the names change.

How to start, step by step

• Get comfortable with Linux commands and basic networking (IP addresses, DNS, ports). Cloud work happens in a terminal.
• Create a free-tier account on one provider and set a billing alert on the first day, so a forgotten server never surprises you.
• Deploy something small: a static website, then a simple API with a database.
• Learn identity and access (IAM). Most real cloud mistakes are about permissions, not code.
• Delete what you create when you finish. Cleaning up is part of the skill.

Where to go next

Follow the AWS Cloud Engineer track or the Google Cloud track from basics to advanced, then prove it with reviewed tasks in an AWS cloud internship or a Google Cloud internship.