FoundationsLesson 1 of 1910 min

Hello, Python

What Python is, how a program actually runs, and your first working script.

By the end you will be able to

Explain what an interpreter does with your code
Print text to the console with print()
Write comments that explain your intent

Python is a general-purpose programming language. You write plain text instructions in a file, and a program called the interpreter reads them top to bottom and carries them out immediately.

That "top to bottom, one line at a time" model is the single most useful thing to hold in your head as a beginner. There is no hidden starting point and no magic — execution begins at the first line of the file and walks down.

Your first instruction

print() displays a value. The text inside the quotes is a string — a piece of text. Press Run below and watch the output panel.

Python

Output

Hello, Python!
— expected output; press Run to execute it yourself

Everything to the right of print lives inside parentheses. Those parentheses mean call this thing. print is a function, and calling it with a value hands that value over to be displayed.

You can pass several values at once, separated by commas. Python puts a single space between them.

Python

Output

CodeNest 2026
Line one
Line two
— expected output; press Run to execute it yourself

Comments

A # marks the rest of the line as a comment. Python ignores it completely. Comments are for humans reading the code later — usually you.

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Output

Visible
— expected output; press Run to execute it yourself

Exercise

Print exactly two lines: first Hello, world!, then your own name on the line below it.

Python

Output

Press Run to execute this code.

Check your understanding

0/2 answered

1.What does the Python interpreter do with a line starting with #?
2.What does print("A", "B") display?