Lesson Notes — The Four Pillars of Computational Thinking
Course 1: Computer Literacy / Unit 14: Computational Thinking & Problem Solving / Lesson 1: The Four Pillars of Computational Thinking
Lesson overview
Computational thinking is a way of solving problems that anyone can learn. It is the thinking behind a navigation app, a hospital schedule, and a video game. It rests on four pillars.
The four pillars
| Pillar | What it means | Everyday example |
|---|---|---|
| Decomposition | Breaking a big problem into smaller, easier parts | Planning a party: pick a date, make a guest list, plan food, arrange music |
| Pattern recognition | Noticing what is similar or repeats | Seeing that making any sandwich involves choosing bread, a filling, and a way to put them together |
| Abstraction | Focusing on what matters and ignoring unneeded details | A subway map shows stops and lines, not every street |
| Algorithm | Writing clear, ordered steps that solve the problem | A recipe, or directions to your house |
Try it: making a sandwich
- Decompose: get ingredients, prepare the bread, add the filling, put it together, clean up.
- Find patterns: a peanut butter sandwich and a turkey sandwich follow the same steps with different ingredients.
- Abstract: the color of the plate does not matter, but the type of bread and filling do.
- Write the algorithm: exact steps, such as take two slices of bread from the bag and place them on the plate, open the jar, and so on.
Try it: buying a plane ticket
You could break it into choosing a destination, picking dates, comparing prices, entering traveler information, and paying. Many travel sites follow the same steps, which is a pattern. The site can hide the details of how airlines set prices, which is abstraction, while the booking steps themselves form an algorithm.
Why it matters
These skills help in every subject and job. They also form the base of programming, where you must tell a computer what to do one precise step at a time.
Check your understanding
- Break down the problem “prepare for the first day at a new job” into at least four smaller tasks.
- Give an example of a pattern you notice in two different games.
- What details would you ignore, and what would you keep, in a map that shows how to walk from the cafeteria to the gym?
Use this lesson’s Key Terms page to build your glossary.