In the book, Clarke expertly shows that the Power behind the monolith does not want to hurt Dave in anyway. The monolith creates an environment for Dave to exist in that would not harm him in any way, makes it look like a hotel room, filling it with familiar items to assuage any fear and appear welcoming.
Dave can't believe what he sees, but leaves the pod and explores the room in his suit. He sees the telephone and telephone book, but the phone doesn't work and the telephone book is blank.
He explores more and finds the refridgerator, where there is a variety of packaged food, but it is all "blue substance, of about the weight and texture of bread pudding. Apart from its odd color, it looked quite appetizing."
There are clothes in the closet, which are a bit out of date for Dave's time.
Dave decides to trust the enviroment. "But this is ridiculous, Bowman told himself. I am almost certainly being watched, and I must look an idiot wearing this suit. If this is some kind of intelligence test, I've probably failed already. Without further hesitation, he walked back into the bedroom and began to undo the clamp of his helmet. When it was loose, he lifted the helmet a fraction of an inch, cracked the seal and took a cautious sniff. As far as he could tell, he was breathing perfectly normal air."
He eats the blue food and drinks the water which "..tasted terrible because it had no taste at all; the faucet was supplying pure, distilled water. His unknown hosts were obviously taking no chances with his health."
He showers, dresses and he turns on the television and "All the programs were about two years old. That was around the time TMA-1 had been discovered, and it was hard to believe that this was a pure coincidence. Something had been monitoring the radio waves; that ebon block had been busier than men had suspected."
Refreshed and exhausted, Dave lies down on the bed, turns off the light and "...for the last time, David Bowman slept."
The Power behind the monolith then transforms Dave into the Starchild, the next evolution of man.
In the movie, however, Kubrick shows Dave growing old in the room and dying a natural death. Whether the monolith manipulates time, or Kubrick decided to show the passage of time using the scene cuts where Dave ages, is up to opinion. But Dave ages and dies and then is transformed into the Starchild. Again, however, the room is created as an environment for Dave to exist in prior to his transformation.