let pigments = ["perinone", "cadmium",
    "titanium", "ultramarine", "napthol"];

let i = 0;
// you've seen this already
while(i < pigments.length) {
    console.log(`while ${i}=${pigments[i]}`);
    i++;
}

// you can do the above in one move like this
for(let i = 0; i < pigments.length; i++) {
    console.log(`for ${i}=${pigments[i]}`);
}

// but this is the easiest of all
for(let paint of pigments) {
    console.log(`for-of ${paint}`);
}