Manipulating Complex Objects
What are strings in JavaScript? A string is a sequence of one or more characters that may consist of letters, numbers, or symbols. Strings in JavaScript are primitive data types and immutable, which means they are unchanging.
The Number object represents numerical date, either integers or floating-point numbers. In general, you do not need to worry about Number objects because the browser automatically converts number literals to instances of the number class.
What are booleans in JavaScript? A core mechanic of Javascript is the ability to distinguish between true and false values. The Javascript standard defines true and false values as a unique data type called a Javascript boolean. Javascript booleans may be true , false , or (in certain contexts) a value that evaluates to either true or false.
An array is an object that can store multiple values at once. For example, const words = ['hello', 'world', 'welcome']; Here, words is an array.
What are functions in JavaScript? A function in JavaScript is similar to a procedure—a set of statements that performs a task or calculates a value, but for a procedure to qualify as a function, it should take some input and return an output where there is some obvious relationship between the input and the output.
JavaScript Objects - You have already learned that JavaScript variables are containers for data values.
What is JavaScript data structure? Data structures are formats in Javascript that help access the data in more efficient ways and make modifications when required. This is achieved through data structures as they allow you to organize, store, and manage the data in certain ways.
What is metadata in JavaScript? Metadata is data (information) about data and are typically used to specify character set, page description, keywords, author of the document, and viewport settings. Metadata will not be displayed on the page, but is machine parsable.
var myMusic = [
{
artist: "Billy Joel",
title: "Piano Man",
release_year: 1973,
formats: ["CD", "8T", "LP"],
gold: true
},
{
artist: "Deep Purple",
title: "Smoke on the water",
release_year: 1976,
formats: ["CD", "8T", "LP"]
}
];
console.log(myMusic.length); will equal 2.