In short, when you care that let a variable assigned from a possible null undefined source, and you wish to provide a default value to the variable, use the nullish coalescing operator ??. If you want to avoid messing yourself around with the JavaScript definition of falsy truthy [1], then avoid using ||. nullish coalescing operator ??

Dec 11, 2008 · In JavaScript, the "===" operator should be used for strict equality comparison, while "==" is used for abstract equality comparison.

Jun 7, 2011 · What is the ?: (question mark and colon operator aka. conditional or "ternary") operator and how can I use it?

& is bitwise AND This operator is almost never used in JavaScript. Other programming languages (like C and Java) use it for performance reasons or to work with binary data. In JavaScript, it has questionable performance, and we rarely work with binary data. This operator expects two numbers and returns a number. In case they are not numbers, they are cast to numbers. How …

Novice JavaScript developers need to know that the "not not" operator is using implicitly the original loose comparison method instead of the exact === or !== operators and also the hidden cast operation that is happening behind the scenes and I show it in the example I provide. – Lucky Brain CommentedJan 22, 2021 at 1:33 Add a comment | 6

Mar 29, 2022 · Javascript does have types; and in any case, how is the dollar sign even related to that? It's just a character that happens to be a legal identifier in Javascript.

Dec 6, 2015 · What does the % do in JavaScript? A definition of what it is and what it does would be much appreciated.

Feb 7, 2009 · What is the difference between == and === in JavaScript? I have also seen != and !== operators. Are there more such operators?

Jan 11, 2023 · I understand that in JavaScript you can write: if (A && B) { do something } But how do I implement an OR such as: if (A OR B) { do something }

May 25, 2018 · JavaScript allows upper- and lower-case letters (in a wide variety of scripts, not just English), numbers (but not at the first character), $, _, and others.¹ Prototype, jQuery, and most javascript libraries use the $ as the primary base object (or function).