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Beginner Topic 11 of 50 Software Engineering

Code Reviews

Peer examination of changes before merging.

How it works

A code review is the practice of having teammates examine changes before they are merged, checking correctness, design, readability, tests, security and consistency with standards. Reviews usually happen through pull requests, with comments, suggestions and approvals, supported by automated checks. They spread knowledge, catch defects early and improve shared ownership of the codebase.

Step-by-step walkthrough

  1. The author opens a pull request.
  2. The reviewer reads the diff for bugs, design and clarity.
  3. Comments and questions are posted.
  4. The author updates the code.
  5. The reviewer approves and the change is merged, sharing knowledge too.

Where it is used

Most engineering teams, from startups to large companies, require reviews. Pair programming and mob programming provide similar feedback in real time.

Common pitfall

Large pull requests are reviewed superficially, so keep them small and focused. Harsh or vague comments harm morale, while rubber-stamping misses bugs. Reviewing style that tools could enforce wastes attention. Slow reviews block progress. Be specific and kind, explain the reasoning, separate must-fix from nice-to-have and respond promptly. Authors should explain context in the description.

Where it fits in the course

Code Reviews is topic 11 of 50 in Software Engineering, rated Beginner. It follows Code Style and Readability. The next topic is Unit Testing.

Practice and explore

How to study this topic

  1. Read the explanation above and restate the definition in your own words.
  2. Open the interactive lesson and answer its mini quiz.
  3. Read the common pitfall, then write a short example that avoids it.
  4. Check your understanding in the Software Engineering quiz, and revisit the topic if you miss a question.

Frequently asked questions

What is Code Reviews?
Peer examination of changes before merging. It belongs to Software Engineering and is a beginner-level topic.
Where do people use Code Reviews?
Most engineering teams, from startups to large companies, require reviews.
What is the most common mistake with Code Reviews?
Large pull requests are reviewed superficially, so keep them small and focused.
What should I learn before this topic?
Start with Code Style and Readability, the topic just before it in Software Engineering.
How can I practice it?
Answer the mini quiz in the interactive lesson, then take the Software Engineering quiz.
Is Code Reviews hard to learn?
It is a Beginner topic, so it works as an entry point. If the terms are new, read the explanation twice and try the visualizer before the quiz.
How long does it take to learn Code Reviews?
Most learners can read the explanation and finish the interactive lesson in under an hour. Fluency comes from applying the idea, so plan a few short practice sessions with the quiz.
Which topics are related to Code Reviews?
Code Style and Readability, Unit Testing, Version Control Concepts are closely connected. The full list is in the related topics section of this page.
What should I study after Code Reviews?
Continue with Unit Testing, the next topic in Software Engineering.

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