Day 3 of 30Python Foundations

✍️Strings & Text

🎯 Today's objective

Manipulate text — the raw material of language AI.

📖 Key concepts

Strings hold text in quotes
Concatenation with +, repeat with *
f-strings: f"Hi {name}"
Methods: .upper(), .lower(), .strip(), len()

💻 Try this code

name = "minu"
print(f"Hello, {name.title()}!")
print(name.upper(), "has", len(name), "letters")
print("ha" * 3)

👥 Learn it your way

🧒 Young Explorers

Strings are like beads on a thread — you can join, repeat, and count them.

Your task

Ask for a word and print it in UPPERCASE, in Title Case, and its length.

💼 Professionals

f-strings are the modern formatting standard; prefer them over % and .format().

Your task

Given a messy " John SMITH " string, normalise it to "John Smith" using strip/title.

🤖 AI connection

Language models read text as strings first, then split it into "tokens". Cleaning text (lowercasing, stripping) is the first step of almost every NLP pipeline.

✅ Quick check

What does an f-string let you do?

Embed variables/expressions directly inside a string with {}.

What does len("AI") return?