Python was designed in 1991 by Guido van Rossum to be a language you could read aloud. Three decades later that small aesthetic decision has carried it into nearly every laboratory, trading desk and AI lab on earth. The reason is unromantic: code is read far more often than it is written, and Python's insistence on whitespace, plain words and one obvious way to do most things makes it cheap to read. When a biologist, an economist and a machine-learning engineer all reach for the same notebook, they reach for Python. You do not need to be a programmer to follow it — only to be willing to read carefully.

Consider: name = "Ada"; greeting = f"Hello, {name}."; print(greeting). Three lines, three ideas. The first stores the text 'Ada' in a labelled box called name. The second composes a new piece of text using that box — the f at the front means 'fill in the blanks'. The third hands the result to print, which displays it. That is the whole rhythm of Python: name something, do something with it, show the result. Everything else in this course is variations on that rhythm.

Byte: indentation is the punctuation

Most languages use curly braces to group code. Python uses indentation — the spaces at the start of a line. Lines that belong to the same block must be indented the same amount. It looks strict; it is. But it means correctly indented code is, by construction, correctly structured.

1. 1.In the line price = 9.99, what is price?

   A function being calledA label (variable) holding the value 9.99A reserved Python keywordAn error — variables need a type declaration

2. 2.Why does Python care about indentation?

   Purely cosmetic — it makes code prettierIt is how Python knows which lines belong to which blockOlder terminals required itTo make code run faster