Clean Code and SOLID Principles in JavaScript: Free Course

About this course

Study Clean Code and SOLID Principles in JavaScript through this free English video course from freeCodeCamp. The classroom brings together all 8 public recordings from the selected source curriculum, totaling approximately 56m. You can watch the teaching sequence, search the lesson list and keep track of the recordings you have completed. The course focuses on the subject named in its title. Its value comes from following the explanations and making your own small practice attempts, with enough time to inspect the result and explain the decisions involved.

Course at a glance

What you’ll learn

• Choose clearer variable and function names
• Explain focused function responsibilities
• Compare object and class organization
• Use SOLID as a reasoning framework
• Discuss testing, concurrency and error handling
• Improve formatting and comments without hiding behaviour

Skills you’ll gain

• Clean code
• JavaScript
• SOLID
• Refactoring

Course Overview

Eight lessons progress through variables, functions, objects, classes, SOLID, tests, errors and formatting.

The source lesson list includes “Clean Code: Variables – Beau teaches JavaScript”, “Clean Code: Classes – Beau teaches JavaScript”, “Clean Code: Formatting and Comments – Beau teaches Javascript”. The classroom retains their original titles and positions. Introductions, supplementary explanations and complete-course recordings remain present whenever they are part of the source. A repeated recording is retained at each original position, allowing the course to be checked against the published teaching sequence.

Names and functions

Start with variables and both function lessons. Explain what a name communicates and compare a small routine before and after separating its responsibilities.

Objects and classes

Follow the object and class material. Identify state and behaviour, then explain why a boundary makes a change easier or harder to understand.

Design principles

Study SOLID in the context of a small example. Connect a principle with the concrete dependency or responsibility it addresses rather than using the name as an automatic rule.

Checks and readability

Follow testing, concurrency, error handling, formatting and comments. Identify an observable result that can be checked, and use a comment to explain a decision rather than repeat the code.

Who is this for?

This course suits learners who want the specific subject described above and who can work at the stated level. It is also useful as a recorded reference when revisiting a concept or comparing a practice attempt with a demonstrated example. Beginners should give the foundational explanations time before moving to more elaborate applications. Experienced learners can use the lesson names to locate a topic, then inspect the surrounding context before applying a technique.

Before you start

Basic JavaScript programming is recommended. Bring a small practice program you understand; the course is most useful when a proposed improvement can be compared with the original behaviour.

Put the lessons into practice

Refactor a fictional catalogue-filtering function. Improve its names, separate one responsibility and keep the original results unchanged for several sample inputs. Add a test for an empty catalogue and an invalid query. Explain one design choice using a principle from the course. Finish with a brief comparison showing which changes improve clarity and which would add unnecessary structure to the example.

Treat this suggested exercise as independent practice provided by WikiFree. Keep a short working note containing your inputs, assumptions, result and one point you still need to check. Revisit the relevant recording when a step is unclear, then attempt a small variation without following the demonstration line by line. A result you can explain and reproduce is a more useful study outcome than simply recognizing a familiar term. The exercise is not submitted to an instructor for grading.

Certificate / Assessment

Watching these public recordings and using WikiFree completion tracking does not award a certificate, academic credit, an examination voucher or instructor assessment. The video curriculum is the material included here. Separate platform assignments, credentials and paid services are not part of video viewing. Use the practice output to review which concepts you can explain, which steps you can repeat independently and which questions need another look at the teaching.

Frequently asked questions

Provider: freeCodeCamp. Videos play from the freeCodeCamp channel on YouTube.