Node js write to file

When using file systems writeFile function, a new file is created when the writeFile method is executed.

var path = require('path');
var fs = require('fs');

var filePath = path.join(__dirname, 'files', 'test.txt');

fs.writeFile(filePath, 'Write text to file, overwrite all.', function(err) {
    if(err) {
        return console.log('Unable to write file ' + err);
    }
    console.log('File was saved');
});