A dog
Knows: its name and its color. Does: sit, bark, run.
14OBJECTS · THINGS
Things that know and do.
In Python, a text or a list is an object. It keeps data (what it knows) and has methods (what it can do).
IN REAL LIFE
Things know stuff and do stuff.
Look around you. Each thing has data (what it knows) and actions (what it does).
A phone
Knows: how much battery is left. Does: call, take a photo.
A backpack
Knows: what is inside. Does: open, close.
LOOK FIRST
Data and actions, joined by a dot.
Data: what it knows
A list knows the things inside it. A text knows its letters.
Methods: what it does
You already used them: word.upper() and toys.append("ball").
The dot
thing.job() asks the thing to do its job. The ( ) means: do it now!
STEP BY STEP
Two objects you already know.
A list and a text. Each one knows things and does things.
toys = ["car", "doll"]An object: a list. Its data is the two toys.toys.append("ball")An action: the list adds a toy to itself.print(toys)The data changed: 3 toys now.word = "robot"Another object: a text. Its data is its letters.print(word.upper())An action that gives back a new text: ROBOTprint(type(word))type() tells what kind of object it is: <class 'str'>. Remember that word class!A secret: In the turtle zone, t = turtle.Turtle() made an object too. t knew its place and its color, and t.forward(50) was its action.
RUN IT
Ask a text to do its jobs.
Guess first. Then run real Python and check.
Guess the result
word = "pybot"
print(word.upper())
print(word.count("b"))
print(type(word))What will the first line show?
OUTPUT
PyBot's hint
Ready. Press Run Python.
Python runs here thanks to Pyodide ♥
Pyodide 314.0.3 runs CPython in your browser with WebAssembly.
Open-source under the Mozilla Public License 2.0. License
Now change one thing: Change "pybot" to your own name and run it. Then try print(type(9)).
YOUR TURN
Know or do?
Try each tiny question. A wrong answer becomes something to review.
0Completed
8Not tried
0Review
A bike
A bike knows its color and how fast it goes. It can ring its bell.
Which one is an action?
A cat's notebook
Michi the cat knows its name and its age.
What are the name and the age?
Ask the list
pets = ["cat"]
pets.append("fish")
print(pets)What does Python show?
Do it now
Which one asks the text to DO its job?
What kind?
print(type("hi"))What does Python show?
Each one its own
a = ["cat"]
b = ["dog"]
a.append("fish")
print(b)What does b show?
Fix PyBot's code
PyBot forgot the ( ), so the action never runs. Python shows something strange instead. Make it show: PYBOT
Goal output
PYBOTOUTPUT
Your work is saved here.
Want a fresh start? Clear only this page.
BIG IDEA
An object is a thing that knows and does.
Its data is what it knows. Its methods are what it can do. Next, you make your own robot mold!