Dialogue is a hallmark of story-driven game and adventure games. Conversation is the foremost way to guide the player through the game as it gives them information about what they are meant to be doing. The dialogue needs to be aware of the narrative in the overarching story and can make or break the immersion for a player.
Role playing games are very popular and when you play a role in a game you personify another character. Game dialogue becomes more interactive when conversations can take different paths. Not only can this dialogue portray the main story line, it can also give various back stories and lore about the world the player is exploring. One common technique employed to give the player a greater illusion of freedom is to have multiple responses lead to the same path. This is usually done to limit the quantity of dialogue to be produced for the game. The branching dialogue usually curves back in on itself that while an individual choice may immediately produce a unique response, the rest of the conversation is typically not unique to that choice.
A good example of great dialogue are games are those that rely heavily on developed characters portraying the main story, whilst at the same time relating to real world emotions. The recent game The Quarry by Supermassive Games is a good example. Having a story that is relatable allows players to develop an attachment to the story and to the characters themselves. This is why it's important to cast appropriately and have directors and writers collaborate to really understand the characters and their inner motives and emotions.
Dialogue is also used to provide information to the player. When dialogue lines are cut above the rest of the mix they can be easily fed to players with directional information which gives time to player to make a decision about how they react to the situation. For example in the game Call of Duty soldiers may shout “grenade” if a grenade lands nearby or “incoming” if an artillery strike is landing on their position.
The video game spectrum is vast, from tiny indie projects with barely any dialogue to massive, high-budget games with lengthy scripts, dozens of characters and even full performance capture that involves full face and body movement. Games with minimal game narrative may still need small bits of dialogue recorded to communicate player information, objectives, progress or encourage the player; including things like "Ready! Game Over! Great Job!" might all be given voice.
