2.1 Syntax, types and control flow

Work through these

• Numbers, strings, booleans, None

  The basic value types and the one that represents nothing at all. Everything else in Python is built from these, and the absent value has its own behaviour worth knowing early.

• Operators, truthiness and comparison chaining

  Operators, which values count as true in a condition, and Python's ability to chain comparisons the way mathematics does. That chaining is unusual and pleasant once you know it exists.

• if/elif/else, while, for, range

  Making decisions and repeating work are the two control structures nearly every program is built from. Almost everything you will write in this subject is these few patterns combined.

• break, continue, else-on-loop

  Leaving a loop early, skipping an iteration, and the clause that runs only if the loop was never interrupted. That last one is a Python peculiarity that reads oddly until explained.