The next() method of AsyncGenerator instances returns the next value in the sequence.

The toLocaleString() method of Array instances returns a string representing the elements of the array. The elements are converted to strings using their toLocaleString methods and these strings are separated by a locale-specific string (such as a comma ",").

The has() method of WeakMap instances returns a boolean indicating whether an element with the specified key exists in this WeakMap or not.

The find() method of TypedArray instances returns the first element in the provided typed array that satisfies the provided testing function. If no values satisfy the testing function, undefined is returned. This method has the same algorithm as Array.prototype.find().

The slice() method of TypedArray instances returns a copy of a portion of a typed array into a new typed array object selected from start to end (end not included) where start and end represent the index of items in that typed array. The original typed array will not be modified. This method has the same algorithm as Array.prototype.slice().

The selectRange() method of Intl.PluralRules instances receives two values and returns a string indicating which plural rule to use for locale-aware formatting of the indicated range.

The getTimeZones() method of Intl.Locale instances returns a list of supported time zones for this locale.

The getHourCycles() method of Intl.Locale instances returns a list of one or more unique hour cycle identifiers for this locale.

The Number.isNaN() static method determines whether the passed value is the number value NaN, and returns false if the input is not of the Number type. It is a more robust version of the original, global isNaN() function.

The Math.atanh() static method returns the inverse hyperbolic tangent of a number. That is,