🐍 Python for Teens & Beginners · Lesson 1 of 7

Your first program

print, quotation marks, and error messages.

print

print("Hello, world!")
print("My name is Sam")
print(7 + 3)

print shows something on the screen. Text goes inside quotation marks; numbers don’t need them. The last line prints 10, not “7 + 3”.

Strings

Text in quotation marks is called a string. "Hello" and 'Hello' both work — just start and end with the same kind. Without quotes, Python thinks the word is a command or a variable.

Error messages are your friends

print("Hello)
# SyntaxError: unterminated string literal

prnt("Hi")
# NameError: name 'prnt' is not defined

An error message says what went wrong and on which line. Read the last line first. Most early errors are a missing quote, a missing parenthesis or a typo.

Comments

# This is a comment. Python ignores it.
print("Comments explain your code")  # one can go here too

Tip

💡 Python is case-sensitive: print works, Print does not.

✏️ Practice: your turn

Print your name, your age and your favorite food on three lines
Print the result of 123 * 4
Make an error on purpose (remove a quote) and read the message
Add a comment explaining your program

✏️ Run Python in your browser, no install ↗

🧠 Quick quiz

Answer all 4 questions correctly to mark this lesson as done.

1. What does print("Hi") do?

2. What does print(2 + 3) show?

3. What is a string?

4. Which line has an error?

0 of 4 correct

👋 Your first program