JavaScript flash cards: Master level
35 JavaScript terms at the Master level, as flash cards.
Updated
Terms in this deck
- Abstract Syntax Tree
- A tree representation of source-code structure used by parsers and tools.
- Accessor Property
- An object property defined by getter and setter functions.
- Call Stack
- The stack of function calls currently being executed.
- Comment node
- A DOM node containing the text of an HTML comment.
- Data Property
- An object property that stores a value directly.
- Document node
- The DOM node representing the whole document and serving as the tree's root.
- Element node
- A DOM node representing an element and its attributes.
- Enumerability
- A property setting that controls whether common enumeration operations include that property.
- Event Loop
- The runtime mechanism that schedules queued work when the call stack is available.
- Execution Context
- The runtime state used to execute a script or function call.
- FinalizationRegistry
- An advanced API for requesting a callback after an object is garbage-collected.
- Garbage Collection
- Automatic recovery of heap memory from objects a program can no longer reach.
- Hidden Class
- An engine optimization that internally groups objects with the same property layout.
- Hoisting
- The effect of declarations being registered before execution reaches their source line.
- Inherited Property
- A property found through an object's prototype chain.
- Inline Cache
- An engine optimization that remembers prior property lookup or call results at a code location.
- Just-in-Time Compilation
- Runtime compilation of frequently executed JavaScript into optimized machine code.
- Lexical Environment
- An internal record connecting names in one scope to values and an outer environment.
- Macrotask
- An informal name for an event-loop task such as a timer or user event.
- Memory Leak
- Unwanted memory growth caused by retaining references to objects no longer needed.
- Microtask Queue
- A high-priority queue used by Promise reactions and queueMicrotask callbacks.
- Node document order
- The order nodes appear when a document tree is traversed from beginning to end.
- Own Property
- A property defined directly on an object rather than inherited.
- Property Descriptor
- A record controlling a property's value, accessors, writability, enumerability, and configurability.
- Prototype
- An object another object consults when a requested property is missing.
- Prototype Chain
- The linked sequence of prototypes searched during property lookup.
- Proxy Object
- An object that intercepts operations such as reading, writing, and property lookup for another object.
- Realm
- A JavaScript execution environment with its own global object and built-in objects.
- Reflect API
- Built-in methods that perform fundamental object operations and pair naturally with Proxy traps.
- Run-to-Completion
- The rule that one JavaScript job finishes before another job begins on the same agent.
- Scope Chain
- The sequence of lexical environments searched to resolve a name.
- Task Queue
- A queue of callbacks waiting to run as event-loop tasks.
- Temporal Dead Zone
- The period where a block-scoped variable exists but cannot be accessed before its declaration.
- Text node
- A DOM node that directly holds a string of characters.
- Weak Reference
- A reference to an object that does not prevent that object from being garbage-collected.