IRB for interactive exploration in Ruby - Mini Project: Build & Apply

Exploring Ruby with IRB

📖 Scenario: You are learning Ruby and want to explore how to use IRB (Interactive Ruby Shell) to try out Ruby commands quickly. IRB lets you type Ruby code and see the results immediately, like a conversation with your computer.

🎯 Goal: Learn how to start IRB, create variables, perform simple calculations, and print results interactively.

📋 What You'll Learn

Start IRB in the terminal

Create a variable called greeting with the value "Hello, IRB!"

Create a variable called number with the value 10

Calculate the square of number and store it in square

Print the value of square

💡 Why This Matters

🌍 Real World

IRB is a tool Ruby developers use daily to quickly test ideas, debug code, and learn Ruby commands without writing full programs.

💼 Career

Knowing how to use IRB helps you become a more efficient Ruby programmer and is a valuable skill in software development jobs that use Ruby.

1

Start IRB and create a greeting variable

Open your terminal and start IRB by typing irb. Then create a variable called greeting and set it to the string "Hello, IRB!".

Ruby

# Start IRB and create greeting variable
greeting = "Hello, IRB!"

Need a hint?

Type irb in your terminal to start. Then type greeting = "Hello, IRB!" and press Enter.

2

Create a number variable

In IRB, create a variable called number and set it to the integer 10.

Ruby

greeting = "Hello, IRB!"
# Create number variable
number = 10

Need a hint?

Type number = 10 and press Enter.

3

Calculate the square of number

In IRB, create a variable called square and set it to the value of number multiplied by itself.

Ruby

greeting = "Hello, IRB!"
number = 10
# Calculate square of number
square = number * number

Need a hint?

Type square = number * number and press Enter.

4

Print the square value

In IRB, print the value of square by typing puts square.

Ruby

greeting = "Hello, IRB!"
number = 10
square = number * number
# Print square value
puts square

Need a hint?

Type puts square and press Enter. You should see 100 printed.