What are the differences between `var` and `let`? Which should I use?

Hi wikiSurfer and core977411,
Refer to the below, it will help you understand better about the use of var and let

here were my instructions: On the line after changeMe is declared, set the value of changeMe to be the boolean false .

I’ve done this: let changeMe = false;

changeMe = true;


I cant seem to understand what I’m suppose to do as I keep getting the “Oops! The test returned an error. Maybe you have a syntax error, or a typo. See full error.” message.

I just ran this code I true is being printed to the console. If you are doing a challenge can you please share the link?

thank you, very understandable and well explained