console.log you can interpolate strings like in PHP's sprintf(). You can also just use the backticks from ES6.
There are a number of methods you can call on the Console object - it's worth checking that list out. One in particular I think is cool:
console.assert(). It only prints if what is inside the parentheses evaluates to true. While developing it could be a good idea to use that for some assumptions you have. If the console stays quiet, you're assuming right!
const date = new Date(); // Nothing is in the console. console.assert(date.getFullYear === date.getFullYear, `Dates don't match`); // See screenshot below. console.assert(date.getFullYear !== date.getFullYear, `Dates don't match`);