Quick def: Reserved words in programming languages (sometimes called keywords) are character strings that have special and specific uses only. Compilers use these words as landmarks when parsing code. Programmers should not name variables, functions, nor classes using these words. Of course, using them in comments is perfectly fine.
There are **LOTS** of keywords in Kotlin. But there's no definitive number because:
1. The definition of keywords (reserved words) in Kotlin is poorly
defined.
2. Kotlin is so new, the number of keywords keeps changing (and not getting smaller!).
The "official" keywords are generally divided up into categories: hard, soft, and operators. Soft keywords are character strings that may be a keyword, depending on the context. Any programmer with any experience will never take the risk of using a soft keyword for obvious reasons. So at the time the number of keywords in Kotlin are
31 (hard) + 48 (soft) + 41 (operators) = some number too big to keep track of
Yup, that's 120 keywords. Or 79 if you don't count operators. By comparison, K&R's C language has 28 keywords with 22 operators = 50. And that's good enough to write Unix.
And we haven't even started talking about *Annotations* (the sly way of slipping in lots and lots of keywords without really having to officially declare them)! Like Kotlin's parent, Java, Kotlin uses Annotations liberally, and there is no limit to the number of them--you can even make your own!
That said, a list of "required" annotations should be included as part of Kotlin's reserved words, but I'm feeling lazy. Let's just say that there are about two dozen. This brings our total of reserved words to... 144 (waaaaay more than I can keep track of). Thanks kotlin, for simplifying my life!