JavaScript Basics
The behaviour underneath the syntax you already recognise: operators, strings, conditionals, loops, functions, arrays and objects. Ten topics of small snippets where the answer is not what the code looks like it says.
Who it is for
Start here. It assumes you can read the language and nothing else.
You will get the most out of it if you have written JavaScript recently enough to read it without effort, and have been surprised by it at least once.
How long it takes
90 graded questions at roughly 45 seconds each is about 68 minutes of answering in total.
At the default five questions a day, and because the session mixes in your other courses, expect around 18 days — call it 3 weeks — to see everything once, plus a few weeks of thinning reviews after that before it is all mastered.
A question is mastered on the third correct answer, once the gap between reviews has grown past a week — so a course cannot be finished in a weekend however long you sit with it.
Question mix
- 80 multiple choice
- 10 concept cards
- 10 matching questions
Syllabus
What you will be asked about
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01
Operators & Precedence
Predict the result of an expression when precedence, not left-to-right reading, decides the grouping.
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02
Strings & Template Literals
Predict what a string method returns, and see where a template literal is converting for you.
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03
Conditionals & Truthiness
Decide which branch runs by knowing exactly which values are falsy.
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04
Loops
Trace how many times a loop body runs and what is left in the loop variable afterwards.
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05
Functions & Return
Say what a function hands back, including the times it quietly hands back undefined.
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06
Arrays: The Basics
Read and change an array by index and length, and know what each basic operation hands back.
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07
Objects: The Basics
Read, add and remove properties, and predict what a missing key gives you.
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08
Type Conversion: The Basics
Convert values on purpose with Number, String and Boolean, and know what each one rejects.
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09
Console & Debugging Basics
Read what the console actually shows you, and choose a log that answers the question you have.
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10
Common Beginner Errors
Spot the mistakes that produce a wrong answer instead of an error message.
A question from this course
Operators & Precedence
What does this print?
console.log(2 + 3 * 4 ** 2);Show the answer
B 50
** goes first (16), then * (48), then + (50). Reading left to right gives 400 — that is the habit to unlearn: precedence decides the grouping before a single value is computed.
The rest of the track
JavaScript at every depth
JavaScript Foundations
Ten topics that cover where JavaScript actually trips people up: scope, coercion, closures, this, async ordering and the modern syntax that replaced the old workarounds.
JavaScript Advanced
The parts of the language that still catch experienced developers: prototypes, proxies, generators, microtask ordering and float arithmetic. Every item is a snippet whose real output is the answer.
Start JavaScript Basics
in tomorrow’s session.
Enrol and this course joins your daily five, mixed in with everything else you are studying — 90 questions spread over about 18 days rather than dropped on you at once.
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