[reddog]

The film — written by Kubrick and Clarke — came first. The book is a novelization of the movie. So watch the movie. It’s unlikely you will be disappointed.

[dredmorbius]

As others have noted, this is false, both were produced concurrently.

Clarke himself provides additional details of the process, as well as omitted excerpts and scenes, in The Lost Worlds of 2001 (1972):

<https://en.wikipedia.org/wiki/The_Lost_Worlds_of_2001>

<https://archive.org/details/lostworldsof20010000arth>

[hencq]

They were written at the same time, but the movie was, indeed, released first. Completely agree that the movie is worth watching. I read the book first, which I felt made the movie more enjoyable for me, since it made the ending a lot more understandable.

[gigatexal]

wait it did?! I did not know that. Amazing. Will do.

[acheron]

No, the post you're responding to is mistaken. They were both written at the same time. It sounds like Clarke and Kubrick got together to hash out the plot and some of the details, then went off and each made their own version. The film was released first (barely, and apparently to the annoyance of Clarke), but the novel was not based on it at all.

[rbanffy]

They were made concurrently, and the movie was released first.