Bring vs Take

Bring and take are two important verbs which are often confused by learners and sometimes natives.They can be interchanged in some cases.

Bring
To bring usually indicates the motion towards the speaker.

- My parents brought me to the America when I was 9 years old.
- Bring me the documents/Bring that documents to me.
- Please bring the pizza over here.

Take
To take usually implies that the object is going away from the speaker.

- When leaving the house, take the umbrella with you.
- He needs someone to take him to the hospital.
- Remember to take the books to the library.

Notice the following sentences:

- Bring the books to school tomorrow.
- Take the books to school tomorrow.

The first sentence indicates that the speaker is either at the school or will be there when the person gets the school .
The second one implies that the speaker will not be in the school.

Usage note excerpt from the American Heritage dictionary :

"In most dialects of American English bring is used to denote motion toward the place of speaking or the place from which the action is regarded: Bring it over here. The prime minister brought a large retinue to Washington with her. Take is used to denote motion away from such a place: Take it over there. The President will take several advisers with him when he goes to Moscow. When the relevant point of focus is not the place of speaking itself, the difference obviously depends on the context. We can say either The labor leaders brought or took their requests to the mayor's office, depending on whether we want to describe things from the point of view of the labor leaders or the mayor. Perhaps for this reason, the distinction between bring and take has been blurred in some areas; a parent may say of a child, for example, She always takes a pile of books home with her from school. This usage may sound curious to those who are accustomed to observe the distinction more strictly, but it bears no particular stigma of incorrectness or illiteracy. •The form brung is common in colloquial use in many areas, even among educated speakers, but it is not standard in formal writing."
http://www.bartleby.com/64/C003/053.html American Heritage Dictionary

When is it correct or incorrect to use them?

1- When it is incorrect to use "bring" and "take" instead of each other:

- Could you please bring me the books.( take is not correct)
- When you come here, remember to bring your camera.(take is not right)
- Please take the books over there.( bring is incorrect)
- When you go there, remember to take your camera over there.

Remember that you must use bring with come and take with go.

2-When it is correct to substitute bring and take for one another:

- She brings his pet to work every day.
- She takes his pet to work every day.

- The ambulance brings people to the hospital.
- The ambulance takes people to the hospital.

- What are you going to take to the party?
- What are you going to bring to the party?

In the above sentences, there is a slight difference between each of two sentences which is usually ignored.