Reference · 20 terms
Glossary
Every short form used across the series. Inside a lesson, hover or tap any dotted term to see the same entry in place.
JavaScript
- async/awaitasync/await
- Syntax that lets you write promise code like straight-line code.Lesson 2 →
- bindcall, apply and bind
- Ways to set this for a function: call and apply run it now, bind returns a new function.Lesson 1 →
- CommonJSCommonJS
- The older Node module system with require and module.exports. Exports are copied values.Lesson 3 →
- ES moduleES module (ESM)
- The standard module system with import and export. Imports are live bindings.Lesson 3 →
- event bubblingEvent bubbling and capturing
- An event travels down to the target (capturing) and back up through its parents (bubbling).Lesson 5 →
- event delegationEvent delegation
- Put one listener on a parent and check event.target, instead of one listener per child.Lesson 5 →
- garbage collectorGarbage collector
- The engine part that frees memory nothing can reach.Lesson 7 →
- generatorGenerator
- A function that can pause at yield and resume later, producing values one at a time.Lesson 4 →
- iteratorIterator and iterable
- An object with a next() method that returns { value, done }. An iterable gives you an iterator.Lesson 4 →
- memory leakMemory leak
- Memory you no longer need but still hold a reference to, so it is never freed.Lesson 7 →
- microtaskMicrotask
- A small job (like a promise callback) that runs when the current code finishes, before timers.Lesson 2 →
- private fieldPrivate field (#name)
- A class field that can be used only inside the class body.Lesson 1 →
- promisePromise
- An object for a value that arrives later. It is pending, then fulfilled or rejected.Lesson 2 →
- property descriptorProperty descriptor
- The settings of a property: value, writable, enumerable and configurable.Lesson 0 →
- prototype chainPrototype chain
- The chain of objects JavaScript follows to find a property that is not on the object itself.Lesson 0 →
- ProxyProxy and Reflect
- A Proxy intercepts actions on another object. Reflect has a function for each basic action.Lesson 6 →
- structuredClonestructuredClone
- A built-in deep copy for many types. It cannot copy functions.Lesson 6 →
- thisthis
- A special value inside a function that depends on how the function was called.Lesson 1 →
- tree shakingTree shaking
- A bundler step that removes exports nobody uses.Lesson 3 →
- WeakMapWeakMap, WeakSet and WeakRef
- Collections and references that do not keep their objects alive.Lesson 7 →