9. JavaScript data types.

There are 8 basic data types in JavaScript.

number for numbers of any kind: integer or floating-point, integers are limited by ±253.
bigint is for integer numbers of arbitrary length.
string for strings. A string may have one or more characters, there’s no separate single-character type.
boolean for true/false.
null for unknown values – a standalone type that has a single value null.
undefined for unassigned values – a standalone type that has a single value undefined.
object for more complex data structures.
symbol for unique identifiers.

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