Is Only `var a = 1;` Truthy in JavaScript's Truthy/Falsy Evaluation?

JavaScript Truthy and Falsy Explained

JavaScript distinguishes values as either truthy or falsy based on their internal representation and semantics. Truthy values translate to true in a Boolean context, while falsy values translate to false.

To clarify the provided code examples:

• var a = 0;: This is falsy because zero is an explicit falsy value.
• var a = 10 == 5;: This is also falsy because (10 == 5) evaluates to false, and any value that evaluates to false is falsy.
• var a = 1;: This is truthy because 1 is a non-zero number. All non-zero numbers, including negative numbers, are truthy.
• var a = -1;: Similarly, this is truthy because -1 is also a non-zero number.

Therefore, the statement "I believe that var a = 1; is the only truthy and the rest are falsy's - is this correct?" is incorrect. Only var a = 1 and var a = -1 are truthy, while the rest are falsy.

It's worth noting that JavaScript has a list of explicit falsy values, which includes: false, null, undefined, 0, NaN, '', and "". Any value not on this list is truthy.

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