Control flow and syntax, compared to what you know

Block structure: indentation, not braces

Most languages mark a block with braces:

if (isReady) {
    printf("this is inside the block\n");
    printf("so is this\n");
}
printf("this is not\n");

Python uses indentation instead — no { }, and the colon (:) opens the block:

Indentation isn’t a style choice here — it’s part of the syntax. Mixing levels inconsistently fails to parse:

There’s also no explicit type declaration on variables — Python is dynamically typed, so x = 5 and x = "five" are both just valid assignments, no int x or var x: string required. (We’ll come back to when you’d want type hints later in the module.)

for loops — iterate over values, not a counter

If you’re coming from a C-style for (int i = 0; i < n; i++), Python’s for works differently: it iterates directly over an iterable — anything that can hand out its items one at a time (a list, a string, a range of numbers). There’s no index variable unless you explicitly ask for one.

tool is each value from the list in turn, not a position. The f"..." string is an f-string: prefixing a string with f lets you embed expressions directly inside { }, evaluated and inserted at runtime — Python’s equivalent of JS template literals or C#’s interpolated strings, and more concise than "available: " + tool or .format().

When you specifically need a counter instead of (or alongside) values, range() generates one — it’s an iterable of numbers, not a special loop syntax: