REPL and print

Learn the REPL and printing with print().

What is the REPL?

REPL stands for Read-Eval-Print Loop. It is the interactive environment that opens when you run the Python interpreter without a file.

In the REPL you type a line, press Enter, and Python runs it immediately and prints the result below. This is very handy for small experiments.

To start the REPL just type python3 in a terminal. To leave, use exit() or press Ctrl+D.

To print something to the screen you use the print function. You put a value or a string inside the parentheses:

print("Hello world")

Strings are written inside double or single quotes. print automatically moves the cursor to a new line after printing.

You can print several values separated by commas: print("Result:", 42).

Write a program that prints Hello world to the screen. Use the print function and a string in double quotes.

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