Why Cloud ?

Every application runs on servers. Depending on the usage, the number of servers may need to be increased or decreased.

But what is a server?
A server is a powerful system that helps you compute, network, store data, and manage users.

Let’s say I am the CEO of an e-commerce app. During a big sale, the number of user logins increases sharply, and our servers crash. To handle the traffic, I purchase a new server. However, during non-sale days, user logins drop, and the extra server remains unused.

In traditional on-premise server setups, this leads to several disadvantages:

• Maintenance is difficult and expensive.

• There is no elasticity (easy scaling up or down).

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How Cloud Computing Solves This

Cloud computing allows pay-as-you-use billing and provides on-demand self-service. The cloud provider manages data centers and infrastructure on our behalf, so we don’t need to worry about hardware maintenance.

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Types of Cloud Services

1. IaaS (Infrastructure as a Service)

• The cloud provider offers virtualized computing resources such as servers, storage, and networking.

• You manage the operating systems, applications, and data.

• Examples: AWS EC2, Microsoft Azure VMs.

2. PaaS (Platform as a Service)

• You focus on developing and deploying applications, while the provider manages infrastructure and runtime environments.

• Examples: Google App Engine, Azure App Service.

3. SaaS (Software as a Service)

• You use software hosted and managed by the cloud provider, usually via a web browser, without managing infrastructure or platforms.

• Examples: Gmail, Salesforce, Microsoft 365.

8/10/2025