Python ships with a huge standard library — code that comes built in, no install needed. This section tours the modules you’ll reach for most often when working with data, files, and time.

What’s in this section

1. math and statistics — common maths and basic stats
2. random — random numbers, choices, shuffles
3. datetime — dates, times, and durations
4. collections — Counter, defaultdict, deque
5. pathlib (deeper look) — work with filesystem paths
6. os and sys — talk to the operating system

Once you know these, you’ll stop reinventing wheels that Python already ships.