Serverless computing basics in Intro to Computing - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is serverless computing?

Serverless computing is a cloud service where you run code without managing servers. The cloud provider handles the servers, so you focus only on your code.

beginner

How does serverless computing save time for developers?

Developers don’t need to set up or maintain servers. They just write and upload code. The cloud runs it automatically when needed.

beginner

What is a real-life analogy for serverless computing?

It’s like ordering food delivery instead of cooking. You get the meal without worrying about buying ingredients or cooking tools.

intermediate

What triggers the execution of code in serverless computing?

Events trigger the code. For example, a user clicking a button or a file upload can start the code automatically.

intermediate

What is a common billing model for serverless computing?

You pay only for the time your code runs, like paying for electricity only when you use it, not for keeping the lights on all day.

Which of these best describes serverless computing?

A Running code only on your personal computer

B Using physical servers in your office

C Running code without managing servers

D Buying and maintaining your own servers

Serverless computing means the cloud provider manages servers, so you only run your code without handling server setup.

In serverless computing, when does your code run?

A Only during business hours

B All the time, 24/7

C When you manually start the server

D Only when triggered by an event

Serverless code runs automatically when an event triggers it, like a user action or a scheduled task.

What is a key benefit of serverless computing for developers?

A No need to manage servers

B Servers are cheaper to buy

C You get a physical server at home

D You must install software on servers

Developers focus on code because the cloud provider manages the servers.

How do you pay for serverless computing?

A A fixed monthly fee regardless of use

B Only for the time your code runs

C By buying server hardware

D Paying for unlimited server time

Billing is based on actual code execution time, making it cost-efficient.

Which event could trigger serverless code to run?

A A user uploading a file

B Turning off your computer

C Installing software locally

D Printing a document

Events like file uploads can automatically start serverless functions.

Explain serverless computing using a real-life analogy.

Think about how you get a service without handling the behind-the-scenes work.

Describe how billing works in serverless computing and why it can save money.

Compare it to paying for electricity only when you use it.

Practice

1. What is the main advantage of serverless computing compared to traditional server management?

easy

A. You don't have to manage or maintain servers yourself.

B. You get unlimited free server usage.

C. You must buy physical servers for your code.

D. You need to install software on each server manually.

Solution

1. Step 1: Understand serverless computing basics

   Serverless computing means the cloud provider manages the servers, so you don't have to.

2. Step 2: Compare with traditional server management

   Traditional requires you to set up and maintain servers; serverless removes this burden.

3. Final Answer:

   You don't have to manage or maintain servers yourself. -> Option A

4. Quick Check:

   Serverless = No server management [OK]

Hint: Serverless means no server setup needed [OK]

Common Mistakes:

• Thinking serverless means free unlimited usage
• Confusing serverless with owning physical servers
• Assuming manual software installation is needed

2. Which of the following is the correct way to describe serverless computing?

easy

A. You run code on your own physical servers.

B. You pay only when your code runs, not for idle time.

C. You must configure the server's operating system manually.

D. You need to buy and maintain server hardware.

Solution

1. Step 1: Identify payment model in serverless

   Serverless charges you only when your code executes, not for idle server time.

2. Step 2: Eliminate incorrect options

   Options A, C, and D describe traditional server management, not serverless.

3. Final Answer:

   You pay only when your code runs, not for idle time. -> Option B

4. Quick Check:

   Serverless payment = pay per execution [OK]

Hint: Serverless billing is based on code execution time [OK]

Common Mistakes:

• Assuming you pay for server uptime even if code is idle
• Confusing serverless with owning physical servers
• Thinking manual OS setup is required

3. Consider this scenario: A serverless function is triggered by a user uploading a photo. What happens immediately after the upload?

medium

A. The serverless function runs automatically to process the photo.

B. The user must manually start the serverless function.

C. The serverless function waits until the server is manually started.

D. The photo upload fails because serverless can't handle files.

Solution

1. Step 1: Understand event-driven nature of serverless

   Serverless functions run automatically when triggered by events like file uploads.

2. Step 2: Analyze the scenario

   Uploading a photo triggers the function immediately without manual intervention.

3. Final Answer:

   The serverless function runs automatically to process the photo. -> Option A

4. Quick Check:

   Serverless = automatic event response [OK]

Hint: Serverless runs code automatically on events [OK]

Common Mistakes:

• Thinking user must start the function manually
• Assuming serverless can't handle file uploads
• Believing server must be manually started first

4. A developer wrote this serverless function code but it never runs when triggered. What is the most likely error?

medium

A. The serverless platform requires manual server start.

B. The function code has a syntax error.

C. The function is not linked to the event trigger.

D. The function runs only on physical servers.

Solution

1. Step 1: Check event trigger linkage

   Serverless functions must be connected to events to run automatically.

2. Step 2: Evaluate other options

   Syntax errors cause failures but usually error messages; manual server start is not needed; serverless does not run only on physical servers.

3. Final Answer:

   The function is not linked to the event trigger. -> Option C

4. Quick Check:

   Missing trigger linkage = no function run [OK]

Hint: Check event trigger connection if function doesn't run [OK]

Common Mistakes:

• Assuming manual server start is needed
• Ignoring event trigger setup
• Confusing serverless with physical server requirements

5. You want to build a photo-sharing app that automatically resizes images when users upload them. Which serverless feature best fits this need?

hard

A. Using physical servers to store photos only.

B. Manually starting servers to process images.

C. Paying for server uptime regardless of uploads.

D. Event-driven functions that run on each photo upload.

Solution

1. Step 1: Identify app requirement

   The app needs automatic image resizing triggered by uploads.

2. Step 2: Match with serverless features

   Event-driven functions run automatically on upload events, perfect for this task.

3. Step 3: Eliminate other options

   Manual server start and paying for uptime are not serverless advantages; physical servers only store, not process.

4. Final Answer:

   Event-driven functions that run on each photo upload. -> Option D

5. Quick Check:

   Event-driven serverless = automatic processing [OK]

Hint: Use event-driven functions for automatic tasks [OK]

Common Mistakes:

• Choosing manual server management
• Ignoring pay-per-use benefits
• Confusing storage with processing