' or " denotes a string
` denotes a template string. Template strings have some abilities that normal strings do not. Most importantly, you get interpolation:
var value = 123;
console.log('test ${value}') //=> test ${value}
console.log(`test ${value}`) //=> test 123
And multiline strings:
console.log('test
test')
// Syntax error
console.log(`test
test`)
// test
// test
They have some other tricks too, more on template strings here: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/template_strings
Note they are not supported in all javascript engines at the moment. Which is why template strings are often used with a transpiler like Babel. which converts the code to something that will work in any JS interpreter.
