Reading local text file into a JavaScript array

I have a text file in the same folder as my JavaScript file. Both files are stored on my local machine. The .txt file is one word on each line like:

red 
green
blue
black

I want to read in each line and store them in a JavaScript array as efficiently as possible. How do you do this?

Using Node.js

sync mode:

var fs = require("fs");
var text = fs.readFileSync("./mytext.txt");
var textByLine = text.split("\n")

async mode:

var fs = require("fs");
fs.readFile("./mytext.txt", function(text){
    var textByLine = text.split("\n")
});

UPDATE

As of at least Node 6, readFileSync returns a Buffer, so it must first be converted to a string in order for split to work:

var text = fs.readFileSync("./mytext.txt").toString('utf-8');

Or

var text = fs.readFileSync("./mytext.txt", "utf-8");