This is, without doubt, a classic staple of science fiction. 2001 stays grounded when it needs to, sticking to an expansion of 60's technology more than trying to imagine some distant future, and catapults you past the distant reaches of plausibility when it wants to. This is, more than the story of Bowman going through some crazy shenanigans on his mission to Saturn's moons, the story of humanity evolving to find a new place in the universe. 

In spite of this, the most gripping part of the story is the classic contention between Bowman and his computer, the HAL 9000, which certainly earns its current state of being integrated into our cultural fabric. The tension in their dialogue, HAL's betrayal and panic and fear, the realization of what caused these issues to manifest, they're all tense and emotional scenes that help to cement a core theme that our humanity is not defined by our bodies. HAL, a mechanical being, has the same human reactions as the rest of us.

The end, after the HAL situation, is a bit crazy. It starts to veer out of the realm of fairly grounded sci-fi and reads as if you're slipping in and out of a fever dream. Nothing is exactly unimaginable, but the constantly shifting scenery makes it hard to keep up and it all just kind of blurs together as a general experience of exploration and realization. Which, honestly, probably works better than trying to carefully take note of everything being shown.

Pretty much anyone with an interest in sci-fi stories should probably go back and read this classic. It imagines a future where humanity actively works to put itself among the stars, and it's refreshing to read something taking an optimistic look at our futures among all the doom and gloom of recent years.