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953---
title: "Computed Property Names: Dynamic Object Keys in JavaScript"
sidebarTitle: "Computed Property Names"
description: "Learn JavaScript computed property names. Create dynamic object keys with variables, expressions, Symbols, and computed methods for cleaner ES6+ code."
---
Have you ever needed to create an object where the property name comes from a variable? Before ES6, this required creating the object first, then adding the property in a separate step. Computed property names changed everything.
```javascript
// Before ES6 - two steps required
const key = 'status';
const obj = {};
obj[key] = 'active';
// ES6 computed property names - single expression
const key2 = 'status';
const obj2 = { [key2]: 'active' };
console.log(obj2); // { status: 'active' }
```
With **computed property names**, you can use any expression inside square brackets `[]` within an object literal, and JavaScript evaluates that expression to determine the property name. This seemingly small syntax addition enables powerful patterns for dynamic object creation.
<Info>
**What you'll learn in this guide:**
- What computed property names are and their ES6 syntax
- How JavaScript evaluates computed keys (order of evaluation)
- Dynamic keys with variables and expressions
- Using Symbol keys for unique, non-colliding properties
- Computed method names, getters, and setters
- Common patterns: form handling, state updates, internationalization
- Edge cases: duplicate keys, type coercion, and the `__proto__` gotcha
</Info>
<Warning>
**Prerequisite:** This guide assumes familiarity with [object basics](/concepts/primitive-types) and [bracket notation](/concepts/modern-js-syntax) for property access. Some examples use [Symbols](/beyond/concepts/javascript-type-nuances), which are covered in detail in the Symbol Keys section.
</Warning>
---
## What are Computed Property Names?
**Computed property names** are an ES6 feature that allows you to use an expression inside square brackets `[]` within an object literal to dynamically determine a property's name at runtime. The expression is evaluated, converted to a string (or kept as a Symbol), and used as the property key. This enables creating objects with dynamic keys in a single expression, eliminating the need for the two-step create-then-assign pattern required before ES6.
```javascript
const field = 'email';
const value = 'alice@example.com';
// The expression [field] is evaluated to get the key name
const formData = {
[field]: value,
[`${field}_verified`]: true
};
console.log(formData);
// { email: 'alice@example.com', email_verified: true }
```
Think of computed property names as **dynamic labels** for your object's filing cabinet. Instead of pre-printing labels (static keys), you're using a label maker (the expression) to print the label right when you create the file.
---
## The Dynamic Label Analogy
Imagine you're organizing a filing cabinet. With traditional object literals, you must know all the label names in advance. With computed properties, you can generate labels on the fly.
```
┌─────────────────────────────────────────────────────────────────────────────┐
│ COMPUTED PROPERTY NAMES: DYNAMIC LABELS │
├─────────────────────────────────────────────────────────────────────────────┤
│ │
│ STATIC KEYS (Traditional) COMPUTED KEYS (ES6) │
│ ───────────────────────── ────────────────────── │
│ │
│ Pre-printed labels: Label maker: │
│ ┌──────────────────┐ ┌──────────────────┐ │
│ │ name: "Alice" │ │ [key]: "Alice" │ │
│ │ age: 30 │ │ [prefix+id]: 30 │ │
│ └──────────────────┘ └──────────────────┘ │
│ │ │
│ You must know "name" key can be any │
│ and "age" at write time expression evaluated │
│ at runtime │
│ │
│ const obj = { const key = 'name'; │
│ name: "Alice", const obj = { │
│ age: 30 ──────────────► [key]: "Alice", │
│ }; [`user_${key}`]: "Alice" │
│ }; │
│ │
└─────────────────────────────────────────────────────────────────────────────┘
```
---
## Basic Syntax
The syntax is straightforward: wrap any expression in square brackets `[]` where you would normally write a property name.
### Variable as Key
The most common use case is using a variable's value as the property name:
```javascript
const propName = 'score';
const player = {
name: 'Alice',
[propName]: 100
};
console.log(player); // { name: 'Alice', score: 100 }
console.log(player.score); // 100
```
### Template Literal as Key
Template literals let you build dynamic key names with string interpolation:
```javascript
const prefix = 'user';
const id = 42;
const data = {
[`${prefix}_${id}`]: 'Alice',
[`${prefix}_${id}_role`]: 'admin'
};
console.log(data);
// { user_42: 'Alice', user_42_role: 'admin' }
```
### Expression as Key
Any valid JavaScript expression works inside the brackets:
```javascript
const i = 0;
const obj = {
['prop' + (i + 1)]: 'first',
['prop' + (i + 2)]: 'second',
[1 + 1]: 'number key'
};
console.log(obj);
// { '2': 'number key', prop1: 'first', prop2: 'second' }
```
### Function Call as Key
You can even call functions to generate key names:
```javascript
function getKey(type) {
return `data_${type}_${Date.now()}`;
}
const cache = {
[getKey('user')]: { name: 'Alice' }
};
console.log(Object.keys(cache)[0]);
// Something like: 'data_user_1699123456789'
```
---
## How the Engine Evaluates Computed Keys
Understanding the evaluation order is crucial for avoiding subtle bugs.
### Order of Evaluation: Key Before Value
When JavaScript encounters a computed property, it evaluates the **key expression first**, then the **value expression**. Properties are processed left-to-right in source order.
```javascript
let counter = 0;
const obj = {
[++counter]: counter, // key: 1, value: 1
[++counter]: counter, // key: 2, value: 2
[++counter]: counter // key: 3, value: 3
};
console.log(obj);
// { '1': 1, '2': 2, '3': 3 }
```
Each property's key expression (`++counter`) is evaluated before its value expression (`counter`), so the key and value end up with the same number.
### Type Coercion: ToPropertyKey()
Property keys can only be **strings** or **Symbols**. When you use any other type, JavaScript converts it using an internal operation called `ToPropertyKey()`:
| Input Type | Conversion |
|------------|------------|
| String | Used as-is |
| Symbol | Used as-is |
| Number | Converted to string: `42` → `"42"` |
| Boolean | `true` → `"true"`, `false` → `"false"` |
| null | `"null"` |
| undefined | `"undefined"` |
| Object | Calls `toString()` → usually `"[object Object]"` |
| Array | Calls `toString()` → `[1,2,3]` becomes `"1,2,3"` |
```javascript
const obj = {
[42]: 'number',
[true]: 'boolean',
[null]: 'null',
[[1, 2, 3]]: 'array'
};
console.log(obj);
// { '42': 'number', 'true': 'boolean', 'null': 'null', '1,2,3': 'array' }
// Number keys and string keys can collide!
console.log(obj[42]); // 'number'
console.log(obj['42']); // 'number' (same property!)
```
<Warning>
**Common gotcha:** Number and string keys that convert to the same string refer to the same property. `obj[1]` and `obj['1']` access the same property.
</Warning>
---
## Before ES6: The Two-Step Pattern
Before computed property names, creating objects with dynamic keys required multiple steps:
```javascript
// ES5: Create object, then add dynamic property
function createUser(role, name) {
var obj = {};
obj[role] = name;
return obj;
}
var admin = createUser('admin', 'Alice');
console.log(admin); // { admin: 'Alice' }
```
This was especially awkward in situations requiring single expressions:
```javascript
// ES5: IIFE pattern for single-expression dynamic keys
var role = 'admin';
var users = (function() {
var obj = {};
obj[role] = 'Alice';
return obj;
})();
// ES6: Clean single expression
const role2 = 'admin';
const users2 = { [role2]: 'Alice' };
```
The ES6 syntax shines in:
- **Default function parameters** that need dynamic objects
- **Arrow functions** with implicit returns
- **Const declarations** requiring immediate initialization
- **Array methods** like `map()` and `reduce()`
```javascript
// ES6 enables elegant patterns
const fields = ['name', 'email', 'age'];
const defaults = fields.reduce(
(acc, field) => ({ ...acc, [field]: '' }),
{}
);
console.log(defaults);
// { name: '', email: '', age: '' }
```
---
## Symbol Keys: The Primary Use Case
Symbols are unique, immutable identifiers that can **only** be used as object keys via computed property syntax. This is one of the most important use cases for computed properties.
### Why Symbols Need Computed Syntax
You cannot use a Symbol with the shorthand or colon syntax:
```javascript
const mySymbol = Symbol('id');
// This creates a string key "mySymbol", NOT a Symbol key!
const wrong = { mySymbol: 'value' };
console.log(Object.keys(wrong)); // ['mySymbol']
// This uses the Symbol as the key
const correct = { [mySymbol]: 'value' };
console.log(Object.keys(correct)); // [] (Symbols don't appear in keys!)
console.log(Object.getOwnPropertySymbols(correct)); // [Symbol(id)]
```
### Symbol Keys Are Hidden
Symbol-keyed properties don't appear in most iteration methods:
```javascript
const secret = Symbol('secret');
const user = {
name: 'Alice',
[secret]: 'classified information'
};
// Symbol keys are hidden from these:
console.log(Object.keys(user)); // ['name']
console.log(JSON.stringify(user)); // '{"name":"Alice"}'
for (const key in user) {
console.log(key); // Only logs 'name'
}
// But you can still access them:
console.log(user[secret]); // 'classified information'
console.log(Object.getOwnPropertySymbols(user)); // [Symbol(secret)]
```
### Well-Known Symbols: Customizing Object Behavior
JavaScript has built-in "well-known" Symbols that let you customize how objects behave. These must be used with computed property syntax.
#### Symbol.iterator: Make Objects Iterable
```javascript
const range = {
start: 1,
end: 5,
[Symbol.iterator]() {
let current = this.start;
const end = this.end;
return {
next() {
if (current <= end) {
return { value: current++, done: false };
}
return { done: true };
}
};
}
};
console.log([...range]); // [1, 2, 3, 4, 5]
for (const num of range) {
console.log(num); // 1, 2, 3, 4, 5
}
```
#### Symbol.toStringTag: Custom Type String
```javascript
const myCollection = {
items: [],
[Symbol.toStringTag]: 'MyCollection'
};
console.log(Object.prototype.toString.call(myCollection));
// '[object MyCollection]'
// Compare to a plain object:
console.log(Object.prototype.toString.call({}));
// '[object Object]'
```
#### Symbol.toPrimitive: Custom Type Coercion
```javascript
const temperature = {
celsius: 20,
[Symbol.toPrimitive](hint) {
switch (hint) {
case 'number':
return this.celsius;
case 'string':
return `${this.celsius}°C`;
default:
return this.celsius;
}
}
};
console.log(+temperature); // 20 (number hint)
console.log(`${temperature}`); // '20°C' (string hint)
console.log(temperature + 10); // 30 (default hint)
```
### Privacy Patterns with Symbols
While not truly private, Symbol keys provide a level of encapsulation:
```javascript
// Module-scoped Symbol - not exported
const _balance = Symbol('balance');
class BankAccount {
constructor(initial) {
this[_balance] = initial;
}
deposit(amount) {
this[_balance] += amount;
}
getBalance() {
return this[_balance];
}
}
const account = new BankAccount(100);
console.log(Object.keys(account)); // []
console.log(JSON.stringify(account)); // '{}'
console.log(account.getBalance()); // 100
// Still accessible if you know about Symbols:
const symbols = Object.getOwnPropertySymbols(account);
console.log(account[symbols[0]]); // 100
```
---
## Computed Method Names
Computed property syntax works with method shorthand for dynamically-named methods:
### Basic Computed Methods
```javascript
const action = 'greet';
const obj = {
[action]() {
return 'Hello!';
},
[`${action}Loudly`]() {
return 'HELLO!';
}
};
console.log(obj.greet()); // 'Hello!'
console.log(obj.greetLoudly()); // 'HELLO!'
```
### Computed Generator Methods
```javascript
const iteratorName = 'values';
const collection = {
items: [1, 2, 3],
*[iteratorName]() {
for (const item of this.items) {
yield item * 2;
}
}
};
console.log([...collection.values()]); // [2, 4, 6]
```
### Computed Async Methods
```javascript
const fetchName = 'fetchData';
const api = {
async [fetchName](url) {
const response = await fetch(url);
return response.json();
}
};
// api.fetchData('https://api.example.com/data')
```
---
## Computed Getters and Setters
You can combine computed property names with [getters and setters](/beyond/concepts/getters-setters):
```javascript
const prop = 'fullName';
const person = {
firstName: 'Alice',
lastName: 'Smith',
get [prop]() {
return `${this.firstName} ${this.lastName}`;
},
set [prop](value) {
const parts = value.split(' ');
this.firstName = parts[0];
this.lastName = parts[1];
}
};
console.log(person.fullName); // 'Alice Smith'
person.fullName = 'Bob Jones';
console.log(person.firstName); // 'Bob'
console.log(person.lastName); // 'Jones'
```
### Symbol-Keyed Accessors
```javascript
const _value = Symbol('value');
const validated = {
[_value]: 0,
get [Symbol.for('value')]() {
return this[_value];
},
set [Symbol.for('value')](v) {
if (typeof v !== 'number') {
throw new TypeError('Value must be a number');
}
this[_value] = v;
}
};
validated[Symbol.for('value')] = 42;
console.log(validated[Symbol.for('value')]); // 42
```
---
## Real-World Use Cases
### Form Field Handling
React and Vue state updates commonly use computed properties:
```javascript
// React-style form handler
function handleInputChange(fieldName, value) {
return {
[fieldName]: value,
[`${fieldName}Touched`]: true,
[`${fieldName}Error`]: null
};
}
const updates = handleInputChange('email', 'alice@example.com');
console.log(updates);
// {
// email: 'alice@example.com',
// emailTouched: true,
// emailError: null
// }
```
### Redux-Style State Updates
```javascript
// Reducer pattern with computed properties
function updateField(state, field, value) {
return {
...state,
[field]: value,
lastModified: Date.now()
};
}
const state = { name: 'Alice', email: '' };
const newState = updateField(state, 'email', 'alice@example.com');
console.log(newState);
// { name: 'Alice', email: 'alice@example.com', lastModified: 1699123456789 }
```
### Internationalization (i18n)
```javascript
function createTranslations(locale, translations) {
return {
[`messages_${locale}`]: translations,
[`${locale}_loaded`]: true,
[`${locale}_timestamp`]: Date.now()
};
}
const spanish = createTranslations('es', { hello: 'hola' });
console.log(spanish);
// {
// messages_es: { hello: 'hola' },
// es_loaded: true,
// es_timestamp: 1699123456789
// }
```
### Dynamic API Response Mapping
```javascript
function normalizeResponse(entityType, items) {
return items.reduce((acc, item) => ({
...acc,
[`${entityType}_${item.id}`]: item
}), {});
}
const users = [
{ id: 1, name: 'Alice' },
{ id: 2, name: 'Bob' }
];
const normalized = normalizeResponse('user', users);
console.log(normalized);
// {
// user_1: { id: 1, name: 'Alice' },
// user_2: { id: 2, name: 'Bob' }
// }
```
---
## Common Mistakes and Edge Cases
### Duplicate Computed Keys: Last One Wins
When multiple computed properties evaluate to the same key, the last one overwrites previous values:
```javascript
const key = 'same';
const obj = {
[key]: 'first',
['sa' + 'me']: 'second',
same: 'third' // Static key, same string
};
console.log(obj); // { same: 'third' }
```
### Keys That Throw Errors
If the key expression throws, object creation is aborted entirely:
```javascript
function badKey() {
throw new Error('Key evaluation failed');
}
// This throws before the object is created
try {
const obj = {
valid: 'ok',
[badKey()]: 'never reached'
};
} catch (e) {
console.log(e.message); // 'Key evaluation failed'
}
```
### Object Keys: toString() Collisions
Objects used as keys call `toString()`, which can cause unexpected collisions:
```javascript
const objA = { toString: () => 'key' };
const objB = { toString: () => 'key' };
const data = {
[objA]: 'first',
[objB]: 'second' // Overwrites! Both → 'key'
};
console.log(data); // { key: 'second' }
```
### The `__proto__` Special Case
The `__proto__` key has special behavior depending on how it's written:
```javascript
// Non-computed: Sets the prototype!
const obj1 = { __proto__: Array.prototype };
console.log(obj1 instanceof Array); // true
console.log(Object.hasOwn(obj1, '__proto__')); // false
// Computed: Creates a normal property
const obj2 = { ['__proto__']: Array.prototype };
console.log(obj2 instanceof Array); // false
console.log(Object.hasOwn(obj2, '__proto__')); // true
// Shorthand: Also creates a normal property
const __proto__ = 'just a string';
const obj3 = { __proto__ };
console.log(obj3.__proto__); // 'just a string' (own property)
```
<Warning>
**Important:** Only the non-computed colon syntax (`__proto__: value`) sets the prototype. Computed `['__proto__']` and shorthand `{ __proto__ }` create regular properties.
</Warning>
---
## Key Takeaways
<Info>
**The key things to remember:**
1. **Computed properties use `[expression]` syntax** in object literals to create dynamic key names at runtime.
2. **The key expression is evaluated before the value expression.** Properties are processed left-to-right in source order.
3. **Non-string/Symbol keys are coerced via ToPropertyKey().** Numbers become strings, objects call `toString()`.
4. **Symbols can ONLY be used as keys via computed property syntax.** The syntax `{ mySymbol: value }` creates a string key `"mySymbol"`.
5. **Well-known Symbols customize object behavior.** Use `[Symbol.iterator]` for iteration, `[Symbol.toStringTag]` for type strings.
6. **Computed method syntax enables dynamic method names.** Works with regular methods, generators, and async methods.
7. **Computed getters/setters enable dynamic accessor properties.** Combine `get [expr]()` and `set [expr](v)` for dynamic accessors.
8. **Pre-ES6 required two steps; ES6 enables single-expression objects.** This is especially useful in `reduce()`, arrow functions, and default parameters.
9. **Duplicate computed keys are allowed—last one wins.** No error is thrown; the later value simply overwrites.
10. **The `__proto__` key behaves differently in computed vs non-computed form.** Only non-computed colon syntax sets the prototype.
</Info>
---
## Test Your Knowledge
<AccordionGroup>
<Accordion title="What's the difference between { key: value } and { [key]: value }?">
**Answer:**
- `{ key: value }` creates a property with the literal name `"key"` (a static string).
- `{ [key]: value }` evaluates the variable `key` and uses its **value** as the property name.
```javascript
const key = 'dynamicName';
const static = { key: 'value' };
console.log(static); // { key: 'value' }
const dynamic = { [key]: 'value' };
console.log(dynamic); // { dynamicName: 'value' }
```
The square brackets signal "evaluate this expression to get the key name."
</Accordion>
<Accordion title="In what order are key and value expressions evaluated?">
**Answer:**
The **key expression is evaluated first**, then the **value expression**. This happens for each property in left-to-right order.
```javascript
let n = 0;
const obj = {
[++n]: n, // key: 1, value: 1
[++n]: n // key: 2, value: 2
};
// { '1': 1, '2': 2 }
```
The `++n` in the key runs before `n` in the value is read, so they match.
</Accordion>
<Accordion title="What happens when you use an object as a computed key?">
**Answer:**
The object is converted to a string via its `toString()` method. By default, this returns `"[object Object]"`, which can cause unintended collisions:
```javascript
const a = { id: 1 };
const b = { id: 2 };
const obj = {
[a]: 'first',
[b]: 'second' // Overwrites! Both → "[object Object]"
};
console.log(obj); // { '[object Object]': 'second' }
```
Custom `toString()` methods can provide unique keys, but this pattern is error-prone. Use Symbols or string IDs instead.
</Accordion>
<Accordion title="Why must Symbol keys use computed property syntax?">
**Answer:**
The shorthand and colon syntax only accept identifiers or string literals as property names. Writing `{ mySymbol: value }` creates a property named `"mySymbol"` (a string), not a Symbol-keyed property.
```javascript
const sym = Symbol('id');
const wrong = { sym: 'value' };
console.log(Object.keys(wrong)); // ['sym'] - string key!
const right = { [sym]: 'value' };
console.log(Object.keys(right)); // [] - Symbol key is hidden
console.log(Object.getOwnPropertySymbols(right)); // [Symbol(id)]
```
The `[sym]` syntax tells JavaScript to evaluate the variable and use the Symbol itself as the key.
</Accordion>
<Accordion title="How do you create a dynamically-named method?">
**Answer:**
Use computed property syntax with method shorthand:
```javascript
const action = 'processData';
const handler = {
[action](data) {
return data.map(x => x * 2);
},
// Generator method
*[`${action}Iterator`](data) {
for (const item of data) {
yield item * 2;
}
},
// Async method
async [`${action}Async`](url) {
const response = await fetch(url);
return response.json();
}
};
console.log(handler.processData([1, 2, 3])); // [2, 4, 6]
```
This works with regular methods, generators (`*[name]()`), and async methods (`async [name]()`).
</Accordion>
<Accordion title="What happens with duplicate computed keys?">
**Answer:**
Duplicate keys are allowed—the **last one wins** and overwrites previous values. No error is thrown:
```javascript
const obj = {
['x']: 1,
['x']: 2,
x: 3
};
console.log(obj); // { x: 3 }
```
This applies whether the duplicate comes from computed properties, static properties, or a mix. The same rule applies to the rest of JavaScript—later assignments overwrite earlier ones.
</Accordion>
</AccordionGroup>
---
## Related Concepts
<CardGroup cols={2}>
<Card title="Modern JS Syntax (ES6+)" icon="wand-magic-sparkles" href="/concepts/modern-js-syntax">
Overview of ES6+ features including destructuring, spread, arrow functions, and enhanced object literals.
</Card>
<Card title="JavaScript Type Nuances" icon="code" href="/beyond/concepts/javascript-type-nuances">
Deep dive into Symbols, a primary use case for computed property keys in JavaScript.
</Card>
<Card title="Getters & Setters" icon="arrows-rotate" href="/beyond/concepts/getters-setters">
Combine computed property names with get and set for dynamic accessor properties.
</Card>
<Card title="Property Descriptors" icon="sliders" href="/beyond/concepts/property-descriptors">
Control writable, enumerable, and configurable flags on your computed properties.
</Card>
<Card title="Object Methods" icon="cube" href="/beyond/concepts/object-methods">
Iterate and transform objects using Object.keys(), entries(), and fromEntries().
</Card>
<Card title="Tagged Template Literals" icon="wand-magic-sparkles" href="/beyond/concepts/tagged-template-literals">
Another ES6+ syntax feature for advanced string processing with template literals.
</Card>
</CardGroup>
---
## References
<CardGroup cols={2}>
<Card title="Object Initializer — MDN" icon="book" href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Object_initializer#computed_property_names">
Official MDN reference for object literals with a dedicated section on computed property names.
</Card>
<Card title="Property Accessors — MDN" icon="book" href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Property_accessors">
Understand bracket notation, the foundation for how computed property names work.
</Card>
<Card title="Symbol — MDN" icon="book" href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Symbol">
Comprehensive reference on Symbols, commonly used with computed property syntax.
</Card>
<Card title="Working with Objects — MDN" icon="book" href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects">
Beginner guide covering object fundamentals and property access patterns.
</Card>
</CardGroup>
---
## Articles
<CardGroup cols={2}>
<Card title="Objects — javascript.info" icon="newspaper" href="https://javascript.info/object#computed-properties">
Excellent tutorial with a dedicated "Computed properties" section and interactive examples.
</Card>
<Card title="ES6 In Depth: Symbols" icon="newspaper" href="https://hacks.mozilla.org/2015/06/es6-in-depth-symbols/">
Mozilla Hacks article explaining Symbols and their use as computed property keys for iterables.
</Card>
<Card title="Exploring ES6: New OOP Features" icon="newspaper" href="https://exploringjs.com/es6/ch_oop-besides-classes.html">
Dr. Axel Rauschmayer's deep technical analysis of computed property keys and ES6 object enhancements.
</Card>
<Card title="Computed Property Names" icon="newspaper" href="https://ui.dev/computed-property-names">
Focused practical article with before/after ES6 comparisons and real-world examples.
</Card>
</CardGroup>
---
## Videos
<CardGroup cols={2}>
<Card title="ES6 JavaScript Tutorial" icon="video" href="https://www.youtube.com/@TraversyMedia">
Traversy Media's comprehensive ES6 coverage including enhanced object literals and computed properties.
</Card>
<Card title="Modern JavaScript Tutorial" icon="video" href="https://www.youtube.com/@NetNinja">
The Net Ninja's series on modern JavaScript features with clear explanations of ES6 syntax.
</Card>
<Card title="JavaScript ES6 Features" icon="video" href="https://www.youtube.com/@WebDevSimplified">
Web Dev Simplified tutorials explaining ES6 features including object shorthand and computed properties.
</Card>
<Card title="JavaScript Quick Tips" icon="video" href="https://www.youtube.com/@Fireship">
Fireship's fast-paced explainers covering JavaScript syntax features and best practices.
</Card>
</CardGroup>