JavaScript · Track

Syntax

Follow the sections in order. Each topic starts with a short explanation before the exercises.

3 levels 29 topics 330 exercises

Learning order

Sections and topics

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Beginner

13 topics · 170 exercises

Conditions Practical exercises on conditional statements in JavaScript: comparing numbers, checking ranges, working with strings, passwords, percentages, and basic if-else logic. 15 tasks Conditions 2 Additional practice with conditionals in JavaScript: string checks, text length, character checks, slicing via string methods, logical operators &&/||, and simple input scenarios. 11 tasks String Methods Learn the built-in string methods in JavaScript — searching, slicing, replacing, splitting, and formatting text with template literals. 10 tasks while loop Exercises on the while loop in JavaScript: repetition of actions, counters, sums of numbers, input to the desired condition, break, string sorting, and basic character processing. 14 tasks For loop and arrays JavaScript for loop practice on arrays: looping through elements, filtering values, counting, finding minimums and maximums, working with strings, dates, and nested data. 15 tasks Functions Basic exercises on functions in JavaScript: function declarations, parameters, return statements, number and string checks, working with arrays and simple calculations. 10 tasks Functions Level 2 Advanced JavaScript function practice: string and number handling, logical tests, arrays, filtering, counting, value searching, and writing reusable functions. 20 tasks Functions Level 3 JavaScript Functions Level 3 Exercises: Functions with modes, flags, multiple conditions, string, array, and number handling to develop algorithmic thinking. 15 tasks OOP Basics Practical exercises on the basics of OOP in JavaScript: creating classes and objects, properties, methods, constructors, changing object state, and simple entity modeling. 11 tasks OOP: Inheritance and Method Overriding OOP problems in JavaScript on inheritance, super(), constructor, method overriding, toString(), custom class methods, and working with objects. 9 tasks OOP, objects, algorithmic thinking JavaScript exercises on OOP, objects, and algorithmic thinking: classes for data analysis, word and character counting, working with ratings, passwords, statistics, and object transformations. 15 tasks Set, objects, error handling JavaScript practice with Sets, objects, and error handling: unique values, common symbols, try/catch, safe data handling, word grouping, and string parsing. 15 tasks Working with files: reading and writing Hands-on exercises for working with files in JavaScript on Node.js: reading text, writing lines, appending data, counting lines and words, processing file contents, and creating simple reports using the fs module. 10 tasks

Intermediate

9 topics · 90 exercises

Array methods: map, filter, reduce Functional array methods for transforming, filtering, and aggregating data without explicit loops. 10 tasks Destructuring and spread Extract values from arrays and objects in one line. Covers destructuring assignment, spread operator, and rest parameters. 10 tasks Arrow Functions & this Master arrow function syntax and understand how `this` behaves differently in arrow functions vs regular functions — a critical distinction for classes, callbacks, and event handlers. 10 tasks Closures Functions that remember their outer scope. Covers closure mechanics and practical patterns like counters and factories. 10 tasks Promises and async/await Handling asynchronous operations with Promise chains, async functions, and await. 10 tasks Regular expressions Pattern matching with RegExp. Covers test, match, replace, and named capture groups. 10 tasks JSON and Date Serializing and deserializing data with JSON, and working with the Date object. 10 tasks Custom errors and error handling Built-in error types, custom Error subclasses, and structured error handling patterns. 10 tasks Map Learn the Map data structure in JavaScript — a key-value collection that accepts any type as a key, preserves insertion order, and provides efficient add, get, and delete operations. 10 tasks

Advanced

7 topics · 70 exercises

Iterators and generators Build custom iterable objects using `Symbol.iterator`, write generator functions with `function*` and `yield`, and use `yield*` to delegate. 10 tasks Modules Work with ES modules: named and default exports/imports, re-exports, dynamic `import()`, and avoiding circular dependencies. 10 tasks The event loop How JavaScript handles concurrency with one thread and one queue at a time. Covers the call stack, task queue, microtask queue, and the order of `setTimeout` vs `Promise.resolve`. 10 tasks Design patterns Reusable solutions to common structural and behavioural problems. Covers Observer, Strategy, Factory, and Decorator pattern in plain JavaScript. 10 tasks Closures and Scope Lexical scope, closures, private state, and closure-based patterns 10 tasks Error Handling Custom errors, try/catch/finally, async errors, and defensive patterns 10 tasks Testing in JavaScript Write and structure unit tests using Jest/Vitest. Covers describe/it/expect, mocking, async tests, and fake timers. 10 tasks