• Forms of storytelling,
  for as long as there has been communication, there has been stories, absolutely countless stories have been told throughout time,  through pictures painted on ancient rock detailing a hunt, to telling your friends how you met a celebrity, there are many ways to tell a story.
  most people assume it's mostly done by books, as that's what you assume when you hear the word story, but thats not true at all, it is in fact mostly done in talking to others, but as of recent
  storys have become interactive, giving the reader the choice to plot the protagonists actions thanks to the magic of videogames

• Game genres.
  there are loads of games, of pretty much every genre, from horror to puzzle.
  more often than not, some games, such as puzzle or FPS dont focus on story telling, but it's not allways the case, the game "Portal" makes a very solid defence.
  
  
• Approaches
  today, stories come in many shapes and sizes, we have the standard storys where the character gets to a problem and solves it only to find a bigger problem.
  but there are many shake ups when it comes to digital media, for example, you could find that in a game, there is barely any story, maybe you're just in a post apocalyptic world with nobody else trying to survive, but you find old family albums, and diarys of long dead people that tell you their tales.
  that is the more interesting thing about interactive storys.
  
  
• Representation,
  most games now have gotten to a point where visuals have met up to reality all the way, where you can see emotion and hardships on a character just from their design.
  some games even push boundries and help real world goals, for example, mass effect has a very open idea of homosexual relationships, which should be accepted, and it forthright accepts it without question.
  in other games there are other social pariahs that are tackled, maybe not in the same way, for example Deus Ex human revolution, this has a very debate-full topic, based in a time where Human augmentation is available, yet not accepted fully.
  it leaves the player considering if it is right or wrong to evolve through machine.
  
• Emotional themes,while games can have their whole overall theme's i would say that in most games it is the different characters that have their own motorvations, rather than a whole cast about revenge.
  
• Interactive story.
  interactive storys are just that, interactive, you are give options in conversation, will you piss the other person off, will you please them. there are just option
  some times though, chosing an option can bar you from choosing others, leading you possibly to lose communication with said character, or even not being able to get a certain ending of a game.
  while it is nice to have a level of freedom, we still have a long way to go before we can make our own speach options rather than a pre-determined set

• Writing strategies 

When writing your own storys there are a number of methods you can use to get the best options, you could write segments, peicing them together as you go, making events as you come up with them.
this can leave you with a lot of left over events that you couldn't use, or expand upon, but it is one method i think works best.

another way which is best for starting up or making a character/scenario is to make a mind map, but there are loads of other methods for loads of different people.