Arrays

Arrays

const fruits = ["mango", "pawpaw", "pineapple"];\nfruits[0];      // "mango"\nfruits.length;  // 3

Adding & removing

fruits.push("orange");  // add to end\nfruits.pop();          // remove from end\nfruits.unshift("banana"); // add to front\nfruits.splice(1, 1);   // remove at index 1

Looping

for (const fruit of fruits) {\n  console.log(fruit);\n}\n\nfruits.forEach((f) => console.log(f));

Common methods

fruits.map(f => f.toUpperCase());  // transform each\nfruits.filter(f => f.length > 5);   // keep matches\nfruits.find(f => f.startsWith("m")); // first match\nfruits.includes("mango");           // true\nfruits.join(", ");                   // "mango, pawpaw, ..."

Mutating vs new

push/pop/splice change the original. map/filter/slice return new arrays. Know which you are using.

Tip: map, filter and reduce do the heavy lifting in modern JS. Learn them early and you will write far less loop code.