It is often said that video games are more similar to films than to the games of the past. While this is as much a reference to the increasingly realistic graphics and the more interactive relationship between your character and others than anything else, there is perhaps another reason behind it.
In the past, video games “happened” a certain way. You would play in one setting, kill a certain kind of enemy and work through to the end of that setting where you would have to kill a really big enemy, who might need to be hit fifty times or more before he’d go away.
Then you would move to the next level, and repeat the process. This “multi-level” system would be very explicit in the game, with opening screens telling you which level you were on.
Now, there is a certain style of game which attracts the description “non-linear”. There are multiple settings, and you move between them as you see fit. To advance the storyline you have to complete certain tasks, but not necessarily in the same order every time.
How you complete those tasks can dictate the future path of the game. Games now are very like films, and while we may not script them we certainly play a part in directing them.
Of course, you will still find multi-level games, which will never die out as long as one set of gamers exists that remembers the joys of PacMan and Donkey Kong. The difference is that the new titles are far more likely to be in the newer style.