A value that is either true or false, used for yes/no decisions in your code.
A boolean is the simplest data type—it is either true or false, nothing in between. Booleans represent yes/no decisions in JavaScript code and are one of the core data types alongside strings, numbers, arrays, and objects.
You create booleans with comparisons (5 > 3 is true) and logical operators. Booleans control which code runs using if statements. Most real-world decisions are boolean: Is the user logged in? Does the password match? Is the list empty? Booleans are stored in variables, passed as props, and included in JSON data.
Booleans are foundational because code constantly makes decisions. Without booleans, everything would execute the same way every time. With them, your code adapts based on conditions.
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