Python, Concept by Concept

Learn Python one idea at a time

13 units, 5 checkpoints, 1 project, in the order the course teaches them.

Printable books (PDF)

Release pdfs-2026-09-30. The links open the files on GitHub.

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Concept mastery

The share of each concept's quiz cards you know well (answered right twice, at least a day apart). Practise with the quiz cards.

All 40 concepts

IO

Printing output0%

Strings

String literals and quotes0%
f-string formatting0%
String concatenation and repetition0%
String slicing0%
String methods (case, strip/replace, split/join, find, is-tests)0%
Membership testing with in0%

Data

Floats and decimal arithmetic0%
Arithmetic operators (+ - * / // %)0%
Type conversion (int/str/float)0%
Boolean values0%

Control

Comparison operators0%
Logical operators (and/or/not)0%
if statements0%
elif and else branches0%

Loops

while loops0%
Loop control (break/continue)0%
for loops0%
The range function0%
Accumulator pattern0%
Nested loops0%

Modules

Importing modules0%
Random numbers (randint/choice)0%

Functions

Defining functions0%
Function parameters and arguments0%
Return values0%
Built-in functions (len/min/max)0%

Collections

Creating lists0%
List indexing (and .index)0%
Growing and changing lists (append/insert/pop/remove)0%
Sorting lists with the sort method0%
Creating dictionaries0%
Looping over dictionaries0%

Files

Reading files0%
Writing files0%
Opening files with with0%

OOP

Defining classes0%
__init__ and creating objects0%
Object attributes0%
Object methods0%