Handwritten notes · Part 1
JavaScript Handwritten Notes for Placements (Free PDF)
By Gaurav SharmaPublished
26 pages of handwritten-style JavaScript notes for placements and interviews: hoisting, closures, this, prototypes, promises, the event loop, polyfills and output-based questions, explained in English with Hinglish.
- Pages
- 26
- Format
- A4 PDF
- Language
- English + Hinglish
- Price
- Free by email
What's inside
23 topics, one page each
- 01How JavaScript runs: engine, runtime, JIT
- 02var, let, const and scope
- 03Hoisting and the Temporal Dead Zone
- 04Primitive vs reference data types
- 05Type coercion, == vs ===, truthy and falsy
- 06Optional chaining, nullish coalescing, spread, rest, destructuring
- 07Functions, arrow functions, higher-order functions, callbacks
- 08Execution context and the call stack
- 09Closures, with interview questions
- 10The this keyword
- 11call, apply, bind and their polyfill
- 12Objects: copying, freezing, methods
- 13Array methods: map, filter, reduce and more
- 14Prototypes, inheritance and classes
- 15Callbacks to Promises
- 16async/await and Promise.all, allSettled, race, any
- 17The event loop: microtasks vs macrotasks
- 18DOM events: bubbling, capturing, delegation
- 19Debounce, throttle, currying, memoization
- 20Polyfills: map, filter, reduce, Promise.all
- 21ES6+ goodies: Map, Set, modules, storage
- 22Output-based questions
- 23Last-minute revision cheat sheet
These are the JavaScript notes I wish I had before my first frontend interview. Each topic fits on one page: the definition you should say out loud, a small code example you can run, the trap that catches most people, and the question interviewers usually ask about it.
What makes these JavaScript notes different?
- One concept per page. No 200-page textbook. Each page is a quick revision you can finish in a few minutes.
- Colour-coded highlights. Yellow for definitions, pink for "asked in almost every interview", green for best practices, orange for traps.
- Hinglish where it helps. Closures,
thisand the event loop get a simple explanation in Hinglish next to the English definition. - Predict-the-output practice. The output-based questions are the ones that show up in online assessments and first-round interviews.
How should you use these JavaScript notes?
Read a page, run its snippet in the browser console, and guess the output before you look at the answer. In the last week before an interview, the final page is a one-page cheat sheet with the ten questions to be able to explain.
Next in the series: the React handwritten notes (Part 3) build on these JavaScript basics, and the C++ handwritten notes cover DSA-round C++ in the same format.
Ready to test yourself? Try the Top 50 JavaScript interview questions with answers, a free PDF with a short answer to say and a detailed explanation for every question.
FAQ
Questions about these notes
Are these JavaScript notes really free?
Yes. The full 26-page PDF is free; email me to request the complete PDF. Share it with friends preparing for placements.
Who are these JavaScript notes for?
Students preparing for campus placements and freshers preparing for frontend, MERN or full-stack interviews. They assume you have written some JavaScript before and want to revise the concepts interviewers actually ask about.
Why are the notes in Hinglish?
Definitions and code are in English, the way you will say them in an interview. The harder ideas, like closures and the event loop, also get a short Hinglish explanation in a purple box, because that is how many of us actually understand things.
Can I print these notes?
Yes. Every page is A4, so the PDF prints cleanly at home or at a print shop.
Placement Series
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