Welcome to Module 1: Make the Computer's Steps Visible

Unit ID: M01-U00 Estimated active time: 8-10 minutes

Let us begin

You do not need to be a programmer before starting this course. You are here to learn how code works, one visible step at a time.

At first, Python can look like a page of punctuation and unfamiliar words. That feeling is normal. We will not begin by asking you to memorise a long list of rules. We will begin with a smaller skill:

Read one line, predict what it will do, run it, and compare the result with your prediction.

That cycle is how we will learn throughout the course.

What you will build

By the end of this module, you will create a small program that summarises fictional daily expenses. The program will:

• store three expense amounts;
• calculate a total and an average;
• show the results clearly; and
• run from the first line to the last without depending on hidden work.

The calculation is simple on purpose. Our focus is not difficult mathematics. Our focus is learning how to give a computer clear steps and check what happened.

A quick starting check

Answer these questions for yourself. They are not graded.

1. Have you run Python code before?
2. Do you know what a notebook cell is?
3. If code fails, do you usually read the error or immediately replace the code?
4. Can you explain why running notebook cells in a different order might change the result?
5. How confident are you about changing a short code example: not confident yet, somewhat confident, or confident?

Keep your answers. At the end of the module, you will look at them again.

Our classroom method

Each lesson follows a simple pattern:

1. Predict: decide what you expect before running the code.
2. Run: ask Python to execute the code.
3. Inspect: read both the output and any error message.
4. Change: alter one small part.
5. Explain: say what changed and why.

Do not rush past the prediction. A correct prediction shows that you understand the step. An incorrect prediction is also useful because it shows exactly what to study.

One important safety rule

Use only the supplied fictional values in this module. Do not enter passwords, account numbers, private messages, work records, health information, or other confidential data into a learning notebook.

What comes next

We will first look at the path from written code to visible output. Once that path is clear, notebook cells and error messages become much less mysterious.