Core knowledge points of JavaScript

I. Language Fundamentals

• Variables and Data Types
• Operators and Expressions
• Control Flow Statements
• Type Conversion and Detection
• Function Basics
• Scope and Closures
• Object Basics
• Array Basics
• Error Handling Mechanisms
• Strict Mode

II. Advanced Functions

• Function Declarations vs. Function Expressions
• Function Parameters and the arguments Object
• Function Invocation and this Binding
• Constructors and the new Operator
• Callback Function Pattern
• Recursive Functions
• Immediately Invoked Function Expressions (IIFE)
• Function Properties and Methods
• Function Currying

III. Objects and Prototypes

• Object Creation Methods
• Property Descriptors
• Object Enumeration and Iteration
• Prototypes and Prototype Chains
• The constructor Property
• Inheritance Implementation
• Object Copying and Comparison
• Method Overriding
• Property Detection

IV. Array Operations

• Array Creation and Initialization
• Basic Array Operations (CRUD)
• Array Traversal Methods
• Array Sorting and Searching
• Array Conversion Methods
• Array Iteration Methods
• Array Reduction Methods
• Sparse Arrays
• Array-like Objects

V. DOM Programming

• DOM Tree Structure
• Node Types and Properties
• DOM Query Methods
• DOM Node Manipulation
• DOM Attribute Operations
• DOM Style Operations
• Event Handling Mechanisms
• Event Object and Event Flow
• Form Element Operations
• DOM Performance Optimization

VI. BOM Operations

• Core window Object APIs
• location Object Operations
• navigator Object Properties
• screen Object Information
• history Object Control
• Timers and Delays
• Dialog Methods
• Browser Detection Methods
• Cookie Operations

VII. Asynchronous Programming

• Single-threaded and Event Loop
• Callback Function Pattern
• setTimeout and setInterval
• Ajax Basics
• JSONP Principles
• Cross-origin Request Handling
• Asynchronous Error Handling
• Asynchronous Flow Control
• Event Listener Pattern

VIII. Advanced Features

• Scope Chain Explained
• Closure Use Cases
• this Binding Rules
• Execution Context and Variable Object
• Garbage Collection Mechanism
• Memory Leak Issues
• Functional Programming Basics
• Design Pattern Implementations
• Performance Optimization Techniques