What's a method you wish you knew earlier in your career working with Javascript or Typescript?

[wiktoriavh]

What did you wish you knew way earlier when you started working with Javascript?

There are so many different ones and I definitely don’t know them all by heart. But one I appreciate a lot is the Intl, which can do various things with numbers. Easy way to represent currencies to the user!

[Eflat_Major]

I didn’t know functional array methods for quite some time like map(), filter(), reduce() etc.. They can make imperative style code way more readable and understandable.