Environments makes games, they are perhaps the most important aspect of game design in my opinion as they control game play and visually instruct and stimulate the user into believing or more importantly enjoying the experience. Environments are artificially created to support game play and they go hand in hand with atmosphere and the pace of game play. They can divide areas, create mood and allow story and emotions to be felt by the player. Environments dictate genre, style and platform and work in different ways to engage the user into believing what they are playing and making the experience more full.
Although environments may not be the first thing people talk about it is usually the first aspect of a game you notice. You are pulled into a game from the start and a sprawling world awaits your eyes. It is this moment that defines game plays the initial feeling and reaction that the player receives when playing and area or level for a first or thirty first time. That is what an environment is, it doesn't have to be blindingly obvious but its role is to interact with the story to show emotion and fit in with the style of the game. Level designers construct areas to slow down the user and create events that make the game more playable and enjoyable. They use cues to show the player where to go such as a light shaft, cavern, doorway. More broadly a focal point show the player where to go and this helps navigate a player in the right direction.
Environment definitely influences the atmosphere of a game by setting the mood with colour and assets that tell a story of the room or moment to the player. Reinforcing the key game play features and story. I don't feel that a players belief in a world universe is down to its direct realism or stylisation, as you can still be drawn into a world that is completely absurd. If you enjoy or are concentrating on a game your mind will help you feel more comfortable within what you are playing. I do think you have to be careful as an over realistic game will distract the user from the game play if anything is wrong or different and the same can be said for an over stylised game that can distract the user by not having anything realistic in its basis.
But if a developer can do this well both these can create brilliant games and environments. I feel that call of duty has done brilliantly in creating games that have environments that can be played over and over again, the same with halos vast caverns and sprawling meadows, GTA's skyscrapers and industrial parks. I think its fair to say everyone will find something to enjoy in a game environments and it doesn't have to be taken from real life to be enjoyable. Super stylised games attract there own player audience and the environments are eye catching and enjoyable. Think of the mass buy of the Wii that saw so many people creating Mii's. Despite its awful graphics it wasn't brought for that it was brought because stylisation is fun and it allowed people to interact and play together.
Environments are pivotal to game play as they create mood, atmosphere, life, stylisation, direction and speed of play. They are equally important across platforms and genres and they take a lot of reference for film, literature and life. They create worlds that are out of this world and allow people to experience things that they wouldn't otherwise experience. Which is what games do best, and why they are so popular.