Rich User Interface
- Lightweight, interpreted programming language
- Cross-platform compatible
- Integration with other backend and frontend technologies
- Used especially for the development of network-based applications
Properties can usually be changed, added, and deleted, but some are read only.
Writing into an HTML element, using innerHTML.
Writing into the HTML output using document.write().
Writing into an alert box, using window.alert().
Writing into the browser console, using console.log().
The let keyword was introduced in ES6 (2015).
Variables defined with let cannot be Redeclared.
Variables defined with let must be Declared before use.
Variables defined with let have Block Scope.
Temporal Dead Zone is a behaviour that occurs with variables declared using let and const keywords.
It is a behaviour where we try to access a variable before it is initialized.
A temporal dead zone (TDZ) is the area of a block where a variable is inaccessible until the moment the computer completely initializes it with a value.
Object destructuring is a new way to extract elements from an object or an array.
WeakMap is similar to Map with key differences:
The keys and values in weakmap should always be an object.
If there are no references to the object, the object will be garbage collected.
Just like Set, WeakSet is also a collection of unique and ordered elements with some key differences:
Weakset contains only objects and no other type.
An object inside the weakset is referenced weakly. This means, if the object inside the weakset does not have a reference, it will be garbage collected.
Unlike Set, WeakSet only has three methods, add() , delete() and has() .