meaning - What is the difference between "look", "see", and "watch"?

When should I use "look", "see", and "watch"?

I'm watching "Star Trek".
Have you seen "Star Trek"?

Are the examples above correct?

Answer

Here are some simple rules that will help deciding which word to use:

• 
  

  See is used as inactive word; you just see without any effort:

  
  
  
  
  • you have visual impression: "I can see my home over there", "I see trees of green"
  
  
  • you understand: "I see what you mean"
  
  
  
  


• 
  

  Look is used as active word, you make an effort to see:

  
  
  
  
  
  • you try to see: "look at this!" (maybe you have to turn your head or stand up)
  
  
  • you pay an attention: "to look for a baby"
  
  
  • you search for something: "you can look up the word in the dictionary"
  
  
  
  


• 
  

  Watch is also an active word; you also make an effort, but it is for a longer period of time:

  
  
  
  
  • "I'm watching "Star Trek", "I like to go to a zoo and watch tigers playing"
  
  
  • pay attention: Watch the kittens as they may run away.
  
  
  
  
  

Here's an example demonstrating the difference:

I'm looking, but I don't see it.

Back to examples:
I'm watching "Star Trek" — it is a continuous action;
Have you seen "Star Trek"? — it is a question if you ever seen it at all, or do you know about it;

It can be also formulated: Have you watched "Star Trek" all night?, and it will mean that you have spent all night watching a movie.

See also: (1), (2).